bulb MERCEDES-BENZ SPRINTER 2006 User Guide

or until the ignition switch is turned to the Off posi-
tion, whichever occurs first.
A brake wear sensor located at each wheel provides
a hard wired ground input to the instrument cluster
circuitry through the brake wear sense circuit when-
ever the brake linings for that wheel have exceeded
their wear limits. The four normally open brake wear
sensors are connected in parallel between ground and
instrument cluster. The brake wear sensors and their
input circuit to the instrument cluster can be diag-
nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the instrument cluster
circuitry that controls the brake wear indicator, a
diagnostic scan tool is required. Refer to the appro-
priate diagnostic information.
CHARGING INDICATOR
DESCRIPTION
A charging indicator is standard equipment on all
instrument clusters. The charging indicator is located
near the lower edge of the instrument cluster, to the
left of the multi-function indicator display. The
charging indicator consists of the International Con-
trol and Display Symbol icon for ªBattery Charging
Conditionº imprinted within a rectangular cutout in
the opaque layer of the instrument cluster overlay.
The dark outer layer of the overlay prevents the indi-
cator from being clearly visible when it is not illumi-
nated. A red Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against a red field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The charging indicator is ser-
viced as a unit with the instrument cluster.
OPERATION
The charging indicator gives an indication to the
vehicle operator when the electrical system voltage is
too low. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and a hard wired input from the
generator. The charging indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the charging indica-
tor for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position with the engine not run-ning the charging indicator is illuminated by the
instrument cluster as a bulb test.
²Generator Input- Each time the cluster
detects that the voltage of the generator input is 12.7
volts or lower while the engine is running, the charg-
ing indicator will be illuminated. The indicator
remains illuminated until the cluster detects that the
voltage of the generator input is above 12.7 volts, or
until the ignition switch is turned to the Off position,
whichever occurs first.
The generator provides a hard wired input to the
instrument cluster circuitry on the engine running
(D+) circuit. If the instrument cluster turns on the
indicator while the engine is running, it may indicate
that the charging system requires service. The gener-
ator input circuit to the instrument cluster can be
diagnosed using conventional diagnostic tools and
methods. For proper diagnosis of the charging sys-
tem, or the instrument cluster circuitry that controls
the charging indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
CLOCK
DESCRIPTION
An electronic digital clock is standard equipment
on all instrument clusters. In vehicles equipped with
the optional ambient temperature indicator, the clock
indication can be toggled with the ambient tempera-
ture indication on the right side of the multi-function
indicator Liquid Crystal Display (LCD) located near
the lower edge of the instrument cluster, directly
below the speedometer. The clock provides a 12 hour-
based, digital indication of the current hours and
minutes. The indications of the clock are not visible
when the LCD is not illuminated. When illuminated
the indications appear as dark characters silhouetted
against an amber field. When the exterior lighting is
turned Off, the display is illuminated at maximum
brightness. When the exterior lighting is turned On
the display illumination level can be adjusted in con-
cert with the cluster general illumination lighting
using the ª+º (plus) and ª2º (minus) multi-function
indicator push buttons. The clock is serviced as a
unit with the instrument cluster.
OPERATION
The clock gives an indication to the vehicle opera-
tor of the current time. The electronic digital clock is
controlled by the instrument cluster microprocessor
based upon cluster programming. The clock display is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indication
to be viewed when the multi-function indicator Liq-
uid Crystal Display (LCD) is activated. However, the
8J - 14 INSTRUMENT CLUSTERVA

clock remains functional regardless of the ignition
switch position.
The vehicle operator can choose to have the
optional ambient temperature indicator displayed
instead of the clock information, but the clock and
ambient temperature indicator cannot be displayed
at the same time. The clock or ambient temperature
indicator display option is selected using the multi-
function indicator clock switch on the instrument
cluster circuit board. This switch is actuated manu-
ally by depressing the clock switch push button that
extends through the lower edge of the cluster lens
below the left end of the multi-function indicator.
Actuating this switch momentarily will toggle the
display between the clock and ambient temperature
indicator modes. Actuating this switch twice within
about one second will cause the display to toggle, but
then automatically revert to the originally selected
mode after about twenty seconds.
See the owner's manual in the vehicle glove box for
more information on the features, use, operation and
setting procedures for the clock. For proper testing of
the instrument cluster circuitry that controls the
clock functions, a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.
COOLANT LOW INDICATOR
DESCRIPTION
A coolant low indicator is standard equipment on
all instrument clusters. The coolant low indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
coolant low indicator consists of the International
Control and Display Symbol icon for ªLow Engine
Coolantº imprinted within a rectangular cutout in
the opaque layer of the instrument cluster overlay.
The dark outer layer of the overlay prevents the indi-
cator from being clearly visible when it is not illumi-
nated. A red Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against a red field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The coolant low indicator is ser-
viced as a unit with the instrument cluster.
OPERATION
The coolant low indicator gives an indication to the
vehicle operator when the engine coolant level is low.
This indicator is controlled by a transistor on the
instrument cluster circuit board based upon cluster
programming and a hard wired input received by the
cluster from the engine coolant level switch. The cool-
ant low indicator Light Emitting Diode (LED) is com-
pletely controlled by the instrument cluster logiccircuit, and that logic will only allow this indicator to
operate when the instrument cluster detects that the
ignition switch is in the On position. Therefore, the
LED will always be off when the ignition switch is in
any position except On. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the coolant low indicator for the following
reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the coolant low indicator is
illuminated for about two seconds as a bulb test.
²Engine Coolant Level Switch Input- Each
time the cluster detects an appropriate input on the
low coolant fluid level sense circuit (engine coolant
level switch resistance low = engine coolant level low)
while the ignition switch is in the On position, the
coolant low indicator will be illuminated. The indica-
tor remains illuminated until the low coolant fluid
level sense input to the cluster changes (engine cool-
ant level switch resistance high = engine coolant
level full), or until the ignition switch is turned to
the Off position, whichever occurs first. The engine
coolant level switch also features a diagnostic resis-
tor connected in parallel between the switch input
and output to provide the cluster with verification
that the low coolant fluid level sense circuit is not
open or shorted.
The engine coolant level switch integral to the cool-
ant bottle provides a hard wired input to the instru-
ment cluster circuitry through the low coolant fluid
level sense circuit. The engine coolant level switch
and the low coolant fluid level sense circuit to the
instrument cluster can be diagnosed using conven-
tional diagnostic tools and methods. For proper diag-
nosis of the instrument cluster circuitry that controls
the coolant low indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
ENGINE TEMPERATURE
GAUGE
DESCRIPTION
An engine coolant temperature gauge is standard
equipment on all instrument clusters. The engine
coolant temperature gauge is located in the upper
right corner of the instrument cluster, to the right of
the speedometer. The engine coolant temperature
gauge consists of a movable gauge needle or pointer
controlled by the instrument cluster circuitry and a
fixed 45 degree scale on the cluster overlay that
reads left-to-right from 120É C to 40É C for Canadian
vehicles, or from 250É F to 110É F for United States
vehicles. An International Control and Display Sym-
bol icon for ªEngine Coolant Temperatureº is located
VAINSTRUMENT CLUSTER 8J - 15

on the cluster overlay, directly below the high end of
the scale. Just to the right of the icon, the nomencla-
ture ªÉCº or ªÉFº confirms the unit of measure for the
gauge readings.
The engine coolant temperature gauge graphics are
white against a black field, except for a single red
graduation at the far left (high) end of the gauge
scale, making them clearly visible within the instru-
ment cluster in daylight. When illuminated from
behind by the panel lamps dimmer controlled cluster
illumination lighting with the exterior lamps turned
On, the white graphics appear amber and the red
graphics appear red. The orange gauge needle is
internally illuminated. Gauge illumination is pro-
vided by Light Emitting Diode (LED) units soldered
onto the instrument cluster electronic circuit board.
The engine coolant temperature gauge is serviced as
a unit with the instrument cluster.
OPERATION
The engine coolant temperature gauge gives an
indication to the vehicle operator of the engine cool-
ant temperature. This gauge is controlled by the
instrument cluster circuit board based upon cluster
programming and electronic messages received by
the cluster from the Engine Control Module (ECM)
over the Controller Area Network (CAN) data bus.
The engine coolant temperature gauge is an air core
magnetic unit that receives battery current on the
instrument cluster electronic circuit board when the
instrument cluster detects that the ignition switch is
in the On position. The cluster is programmed to
move the gauge needle back to the low end of the
scale after the ignition switch is turned to the Off
position. The instrument cluster circuitry controls
the gauge needle position and provides the following
features:
²Engine Temperature Normal Message- Each
time the cluster receives a message from the ECM
indicating the engine coolant temperature is within
the normal operating range [up to about 120É C (250É
F), the gauge needle is moved to the actual relative
temperature position on the gauge scale.
²Engine Temperature High Message- Each
time the cluster receives a message from the ECM
indicating the engine coolant temperature is high
[above about 120É C (250É F) the gauge needle is
moved into the red warning zone on the gauge scale.
The ECM continually monitors the engine coolant
temperature sensor to determine the engine operat-
ing temperature. The ECM then sends the proper
engine coolant temperature messages to the instru-
ment cluster. If the instrument cluster moves the
engine coolant temperature gauge needle to red area
of the gauge scale, it may indicate that the engine or
the engine cooling system require service. For proper
diagnosis of the engine coolant temperature sensor,
the ECM, the CAN data bus, the electronic messageinputs to the instrument cluster, or the instrument
cluster circuitry that controls the engine coolant tem-
perature gauge, a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.
ESP INDICATOR
DESCRIPTION
An Electronic Stability Program (ESP) indicator is
standard equipment on all instrument clusters, but is
only functional on vehicles equipped with the
optional ESP system. The ESP indicator is located
near the lower edge of the instrument cluster, to the
right of the multi-function indicator display. The ESP
indicator consists of a stencil-like cutout of the text
ªESPº in the opaque layer of the instrument cluster
overlay. The dark outer layer of the overlay prevents
the indicator from being clearly visible when it is not
illuminated. An amber Light Emitting Diode (LED)
behind the cutout in the opaque layer of the overlay
causes the text to appear in amber through the
translucent outer layer of the overlay when the indi-
cator is illuminated from behind by the LED, which
is soldered onto the instrument cluster electronic cir-
cuit board. The ESP indicator is serviced as a unit
with the instrument cluster.
OPERATION
The ESP indicator gives an indication to the vehi-
cle operator when the ESP system is faulty or inop-
erative. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and electronic messages received by
the cluster from the Controller Antilock Brake (CAB)
over the Controller Area Network (CAN) data bus.
The ESP indicator Light Emitting Diode (LED) is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indicator to
operate when the instrument cluster detects that the
ignition switch is in the On position. Therefore, the
LED will always be off when the ignition switch is in
any position except On. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the ESP indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the ESP indicator is illu-
minated by the cluster for about two seconds as a
bulb test.
²ESP Lamp-On Message- Each time the clus-
ter receives a lamp-on message from the CAB, the
ESP indicator will be illuminated. The indicator
remains illuminated until the cluster receives a
lamp-off message from the CAB, or until the ignition
switch is turned to the Off position, whichever occurs
first.
8J - 16 INSTRUMENT CLUSTERVA

The CAB continually monitors the ESP circuits
and sensors to decide whether the system is in good
operating condition. The CAB then sends the proper
lamp-on or lamp-off messages to the instrument clus-
ter. If the CAB sends a lamp-on message after the
bulb test, it indicates that the CAB has detected a
system malfunction and/or that the ESP system has
become inoperative. The CAB will store a Diagnostic
Trouble Code (DTC) for any malfunction it detects.
For proper diagnosis of the ESP system, the CAB,
the CAN data bus, the electronic message inputs to
the instrument cluster, or the instrument cluster cir-
cuitry that controls the ESP indicator, a diagnostic
scan tool is required. Refer to the appropriate diag-
nostic information.
FUEL FILTER CLOGGED INDI-
CATOR
DESCRIPTION
A fuel filter clogged indicator is standard equip-
ment on all instrument clusters. The fuel filter
clogged indicator is located near the left edge of the
instrument cluster, next to the tachometer. The fuel
filter clogged indicator consists of the International
Control and Display Symbol icon for ªFuel Filterº
imprinted within a rectangular cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. An
amber Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the icon to
appear silhouetted against an amber field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The fuel filter clogged indicator
is serviced as a unit with the instrument cluster.
OPERATION
The fuel filter clogged indicator gives an indication
to the vehicle operator when the pressure in the fuel
system is low, which could indicate that the fuel filter
is clogged. This indicator is controlled by a transistor
on the instrument cluster circuit board based upon
cluster programming and electronic messages
received by the cluster from the Engine Control Mod-
ule (ECM) over the Controller Area Network (CAN)
data bus. The fuel filter clogged indicator Light Emit-
ting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided apath to ground by the instrument cluster transistor.
The instrument cluster will turn on the fuel filter
clogged indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the fuel filter clogged indi-
cator is illuminated by the cluster for about two sec-
onds as a bulb test.
²Fuel Filter Clogged Lamp-On Message-
Each time the cluster receives a lamp-on message
from the ECM, the fuel filter clogged indicator will
be illuminated. The indicator remains illuminated
until the cluster receives a lamp-off message from
the ECM, or until the ignition switch is turned to the
Off position, whichever occurs first.
The ECM continually monitors the low fuel pres-
sure sensor located at the inlet of the high pressure
fuel pump to decide whether the fuel system is in
good operating condition. The ECM then sends the
proper lamp-on or lamp-off messages to the instru-
ment cluster. If the ECM sends a lamp-on message
after the bulb test, it indicates that the ECM has
detected a low pressure condition in the fuel system,
which could result from a clogged fuel filter or from
any other restrictions in the fuel delivery system.
The ECM will store a Diagnostic Trouble Code (DTC)
for any malfunction it detects. For proper diagnosis
of the low fuel pressure sensor, the ECM, the CAN
data bus, the electronic message inputs to the instru-
ment cluster, or the instrument cluster circuitry that
controls the fuel filter clogged indicator, a diagnostic
scan tool is required. Refer to the appropriate diag-
nostic information.
FUEL GAUGE
DESCRIPTION
A fuel gauge is standard equipment on all instru-
ment clusters. The fuel gauge is located in the lower
right corner of the instrument cluster, to the right of
the speedometer. The fuel gauge consists of a mov-
able gauge needle or pointer controlled by the instru-
ment cluster circuitry and a fixed 45 degree scale on
the cluster overlay that reads left-to-right from ªFº
(or Full) to ªEº (or Empty). An International Control
and Display Symbol icon for ªFuelº is located on the
cluster overlay, directly to the left of the low end of
the scale.
The fuel gauge graphics are white against a black
field, making them clearly visible within the instru-
ment cluster in daylight. When illuminated from
behind by the panel lamps dimmer controlled cluster
illumination lighting with the exterior lamps turned
On, the white graphics appear amber. The orange
gauge needle is internally illuminated. Gauge illumi-
nation is provided by Light Emitting Diode (LED)
units soldered onto the instrument cluster electronic
VAINSTRUMENT CLUSTER 8J - 17

required. Refer to the appropriate diagnostic infor-
mation.
HIGH BEAM INDICATOR
DESCRIPTION
A high beam indicator is standard equipment on
all instrument clusters. The high beam indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
high beam indicator consists of the International
Control and Display Symbol icon for ªHigh Beamº
imprinted within a rectangular cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. A
blue Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the icon to
appear silhouetted against a blue field through the
translucent outer layer of the overlay when the indi-
cator is illuminated from behind by the LED, which
is soldered onto the instrument cluster electronic cir-
cuit board. The high beam indicator is serviced as a
unit with the instrument cluster.
OPERATION
The high beam indicator gives an indication to the
vehicle operator whenever the headlamp high beams
are illuminated. This indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and a hard wired
input from the multi-function switch. The high beam
indicator Light Emitting Diode (LED) is completely
controlled by the instrument cluster logic circuit, and
that logic will allow this indicator to operate when-
ever the instrument cluster receives battery current
on the fused B(+) circuit. Therefore, the LED can be
illuminated regardless of the ignition switch position.
The LED only illuminates when it is provided a path
to ground by the instrument cluster transistor. The
instrument cluster will turn on the high beam indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the high beam indicator is
illuminated by the cluster for about two seconds as a
bulb test.
²High Beams On Input- Each time the cluster
receives a high beam headlamps-on input from the
multi-function switch, the high beam indicator will
be illuminated. The indicator remains illuminated
until the cluster receives a high beam headlamps-off
input from the multi-function switch.
The instrument cluster continually monitors the
multi-function switch input to determine whether the
high beam indicator should be illuminated or extin-
guished. The multi-function switch and the multi-
function switch input circuit to the instrumentcluster can be diagnosed using conventional diagnos-
tic tools and methods. For proper diagnosis of the
instrument cluster circuitry that controls the high
beam indicator, a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.
LOW FUEL INDICATOR
DESCRIPTION
A low fuel indicator is standard equipment on all
instrument clusters. The low fuel indicator is located
directly below the low end of the fuel gauge scale.
The low fuel indicator consists of a small triangular
cutout in the opaque layer of the instrument cluster
overlay. The dark outer layer of the overlay prevents
the indicator from being clearly visible when it is not
illuminated. An amber Light Emitting Diode (LED)
behind the cutout in the opaque layer of the overlay
causes the triangle to appear in amber through the
translucent outer layer of the overlay when the indi-
cator is illuminated from behind by the LED, which
is soldered onto the instrument cluster electronic cir-
cuit board. The low fuel indicator is serviced as a
unit with the instrument cluster.
OPERATION
The low fuel indicator gives an indication to the
vehicle operator when the level of fuel in the fuel
tank becomes low. This indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and a hard wired
input received by the cluster from the fuel level sen-
sor in the fuel tank. The low fuel indicator Light
Emitting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the low fuel indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the low fuel indicator is
illuminated for about two seconds as a bulb test.
²Fuel Level Sensor Input- Each time the clus-
ter receives an input from the fuel level sensor indi-
cating that the fuel level has reached about 12 liters
(3 gallons) or less, the low fuel indicator is illumi-
nated. The indicator remains illuminated until the
cluster receives an input from the fuel level sensor
indicating that the fuel level is above 12 liters (3 gal-
lons), or until the ignition switch is turned to the Off
position, whichever occurs first.
The fuel level sensor in the fuel tank provides a
hard wired input to the instrument cluster circuitry
VAINSTRUMENT CLUSTER 8J - 19

through the fuel level sense circuit. The fuel level
sensor is a potentiometer that changes resistance
according to the fuel level. As the fuel level
decreases, the resistance through the fuel level sen-
sor increases. The instrument cluster applies a fuel
tank characteristic curve and fuel tank reserve valve
setting to the fuel level sensor input, which must be
configured when the cluster is initialized. These
characteristics determine the algorithm the cluster
uses to display the fuel level data on the fuel gauge
and the control for the low fuel warning indicator.
The fuel level sensor and the fuel level sense circuit
to the instrument cluster can be diagnosed using con-
ventional diagnostic tools and methods. For proper
diagnosis of the instrument cluster circuitry that con-
trols the fuel gauge, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
LOW OIL LEVEL INDICATOR
DESCRIPTION
A low oil level indicator is standard equipment on
all instrument clusters. The low oil level indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
low oil level indicator consists of the International
Control and Display Symbol icon for ªEngine Oilº
imprinted within a rectangular cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. A red
Light Emitting Diode (LED) behind the cutout in the
opaque layer of the overlay causes the icon to appear
silhouetted against a red field through the translu-
cent outer layer of the overlay when the indicator is
illuminated from behind by the LED, which is sol-
dered onto the instrument cluster electronic circuit
board. The low oil level indicator is serviced as a unit
with the instrument cluster.
OPERATION
The low oil level indicator gives an indication to
the vehicle operator when the engine oil level is low.
This indicator is controlled by a transistor on the
instrument cluster electronic circuit board based
upon cluster programming and electronic messages
received by the cluster from the Engine Control Mod-
ule (ECM) over the Controller Area Network (CAN)
data bus. The low oil level indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path toground by the instrument cluster transistor. The
instrument cluster will turn on the low oil level indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the low oil level indicator
is illuminated for about two seconds as a bulb test.
²Engine Oil Level Low Message- Once the
engine has been started, each time the cluster
receives a message from the ECM indicating that the
engine oil level is at or near the ªMinimumº mark on
the dipstick, the low oil level indicator is illuminated.
The indicator remains illuminated briefly at first, but
will remain illuminated for longer periods as subse-
quent messages indicate that the oil level has
dropped further. Eventually, the indicator will
remain illuminated solid until the engine oil level is
corrected, or until the ignition switch is turned to the
Off position, whichever occurs first.
The instrument cluster also supplements the oil
level indicator by displaying an engine oil icon along
with alpha-numeric messages in the multi-function
indicator Liquid Crystal Display (LCD) advising the
vehicle operator how much oil is required to correct
the engine oil level, and when the ªMaximumº engine
oil level has been exceeded. See the owner's manual
in the vehicle glove box for more information on this
feature.
The ECM continually monitors the engine oil level
and temperature sensor to determine the engine oil
level. The ECM then sends the proper engine oil
level messages to the instrument cluster. If the
instrument cluster turns on the indicator after the
bulb test, even after the engine oil level is sufficient,
it may indicate that the engine or the engine oiling
system requires service. For proper diagnosis of the
engine oil level and temperature sensor, the ECM,
the CAN data bus, or the electronic message inputs
to the instrument cluster that control the low oil
level indicator, a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.
MAINTENANCE INDICATOR
DESCRIPTION
An Active Service SYSTem (ASSYST) engine oil
maintenance indicator is optional equipment on all
instrument clusters. In vehicles so equipped, a sec-
ond, dedicated ASSYST microprocessor is integral to
the cluster electronic circuit board. The ASSYST indi-
cations are displayed and can be toggled with the
clock indication on the right side of the multi-func-
tion indicator Liquid Crystal Display (LCD) located
near the lower edge of the instrument cluster,
directly below the speedometer. The ASSYST displays
include numeric values combined with several icons
to indicate actual engine oil level, and reminders in
time (days) or distance (miles or kilometers) until the
8J - 20 INSTRUMENT CLUSTERVA

next required engine oil maintenance is anticipated.
ASSYST also provides several audible indications
using the electronic tone generator on the instrument
cluster circuit board to supplement these visual dis-
plays.
The indications of the ASSYST engine oil mainte-
nance indicator are not visible when the LCD is not
illuminated. When illuminated, the ASSYST indica-
tions appear as dark characters and icons silhouetted
against an amber field. When the exterior lighting is
turned Off, the display is illuminated at maximum
brightness. When the exterior lighting is turned On,
the display illumination level can be adjusted in con-
cert with the cluster general illumination lighting
using the ª+º (plus) and ª2º (minus) multi-function
indicator push buttons. The ASSYST engine oil main-
tenance indicator is serviced as a unit with the
instrument cluster.
OPERATION
The ASSYST engine oil maintenance indicator
microprocessor uses numerous criteria besides time
and mileage to evaluate vehicle maintenance require-
ments. Time data is taken from the electronic digital
clock integral to the instrument cluster. Vehicle dis-
tance data is obtained from the Controller Antilock
Brake (CAB) over the Controller Area Network
(CAN) data bus. Coolant temperature, engine oil
temperature, engine oil level, engine oil quality,
engine speed, and engine load data are obtained from
the Engine Control Module (ECM) over the CAN
data bus. Using all of the available data and internal
programming, the ASSYST microprocessor then cal-
culates the estimated time and distance to the next
required engine oil maintenance interval. The
ASSYST uses the multi-function indicator LCD to
display that data and, when necessary, issues audible
alerts to the vehicle operator through the electronic
tone generator on the cluster circuit board.
See the owner's manual in the vehicle glove box for
more information on the features, use, operation and
resetting procedures for the ASSYST maintenance
computer. Proper diagnosis and testing of the
ASSYST engine oil maintenance computer, the CAN
data bus and the electronic data bus message inputs
to the EMIC that are used by the ASSYST computer
for its calculations requires the use of a diagnostic
scan tool. Refer to the appropriate diagnostic infor-
mation.
MALFUNCTION INDICATOR
LAMP (MIL)
DESCRIPTION
A Malfunction Indicator Lamp (MIL) is standard
equipment on all instrument clusters. The MIL islocated near the lower edge of the instrument cluster,
to the right of the multi-function indicator display.
The MIL consists of the International Control and
Display Symbol icon for ªEngineº imprinted within a
rectangular cutout in the opaque layer of the instru-
ment cluster overlay. The dark outer layer of the
overlay prevents the indicator from being clearly vis-
ible when it is not illuminated. An amber Light
Emitting Diode (LED) behind the cutout in the
opaque layer of the overlay causes the icon to appear
silhouetted against an amber field through the trans-
lucent outer layer of the overlay when the indicator
is illuminated from behind by the LED, which is sol-
dered onto the instrument cluster electronic circuit
board. The MIL is serviced as a unit with the instru-
ment cluster.
OPERATION
The Malfunction Indicator Lamp (MIL) gives an
indication to the vehicle operator when the Engine
Control Module (ECM) has recorded a Diagnostic
Trouble Code (DTC) for an On-Board Diagnostics II
(OBDII) emissions-related circuit or component mal-
function. The MIL is controlled by a transistor on the
instrument cluster circuit board based upon cluster
programming and electronic messages received by
the cluster from the ECM over the Controller Area
Network (CAN) data bus. The MIL Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the MIL for the fol-
lowing reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the MIL is illuminated as a
bulb test. The indicator will remain illuminated until
the engine is started, or until the ignition switch is
turned to the Off position, whichever occurs first.
²MIL Lamp-On Message- Each time the clus-
ter receives a MIL lamp-on message from the ECM,
the indicator will be illuminated. The indicator will
remain illuminated until the detected fault is
repaired, or until the ignition switch is turned to the
Off position, whichever occurs first. For more infor-
mation on the ECM and the DTC set and reset
parameters, (Refer to 25 - EMISSIONS CONTROL -
OPERATION).
²Communication Error- If the cluster receives
no lamp-on or lamp-off message from the ECM, the
MIL is illuminated by the instrument cluster. The
indicator remains controlled and illuminated by the
cluster until a valid lamp-on or lamp-off message is
received from the ECM.
VAINSTRUMENT CLUSTER 8J - 21

The ECM continually monitors the fuel and emis-
sions system circuits and sensors to decide whether
the system is in good operating condition. The ECM
then sends the proper lamp-on or lamp-off messages
to the instrument cluster. If the instrument cluster
turns on the MIL after the bulb test, it may indicate
that a malfunction has occurred and that the fuel
and emissions systems may require service. For
proper diagnosis of the fuel and emissions systems,
the ECM, the CAN data bus, or the electronic mes-
sage inputs to the instrument cluster that control the
MIL, a diagnostic scan tool is required. Refer to the
appropriate diagnostic information.
MULTI - FUNCTION INDICA-
TOR
DESCRIPTION
A multi-function indicator is standard equipment
on all instrument clusters. The multi-function indica-
tor is located near the lower edge of the instrument
cluster, directly below the speedometer. The multi-
function indicator consists of a Liquid Crystal Dis-
play (LCD) unit and four push button-controlled
switches that are soldered onto the instrument clus-
ter electronic circuit board. The LCD is visible
through a large rectangular cutout in the instrument
cluster overlay, while the four switch push buttons
extend through a black plastic switch bezel located
on the cluster lens directly below the LCD. The four
multi-function indicator push buttons allow the vehi-
cle operator to configure and adjust several of the
display features. The buttons are labeled from left to
right: ªmiº (miles) or ªkmº (kilometers), an icon
depicting an analog clock face (clock), ª2º (minus),
and ª+º (plus).
The multi-function indicator LCD displays both
alpha-numeric characters and numerous icons to pro-
vide information to the vehicle operator. The indica-
tions of the multi-function indicator are not visible
when the LCD is not illuminated. When illuminated
the indications appear as dark characters and icons
silhouetted against an amber field. When the exterior
lighting is turned Off, the display is illuminated at
maximum brightness. When the exterior lighting is
turned On the display illumination level can be
adjusted in concert with the cluster general illumina-
tion lighting using the ª+º (plus) and ª2º (minus)
multi-function indicator push buttons. The multi-
function indicator LCD unit and push button
switches are serviced as a unit with the instrument
cluster.
OPERATION
The multi-function indicator has several display
capabilities including odometer, trip odometer, clock,engine oil level data, gear selector indicator
(PRNDL), certain diagnostic information and, on
vehicles so equipped, an optional Active Service SYS-
Tem (ASSYST) engine oil maintenance indicator and
an optional outside ambient temperature indicator.
The multi-function indicator is completely controlled
by the instrument cluster logic circuit, and that logic
will allow this indication to be viewed whenever the
multi-function indicator Liquid Crystal Display
(LCD) is activated. Therefore, the indicator remains
functional regardless of the ignition switch position.
With the ignition switch in the Off or Accessory posi-
tions and the key removed from the ignition lock cyl-
inder, the display is activated when the park lamps
are turned On or, for about thirty seconds after any
one of the multi-function indicator switch push but-
tons is depressed. Otherwise, the display unit is
active for about thirty seconds after the key is
inserted into the ignition lock cylinder, and inactive
about thirty seconds after the key is removed from
the ignition lock cylinder.
The multi-function indicator ªmiº (miles) or
ªkmº(kilometers) switch push button is used to con-
trol the odometer/trip odometer display modes. The
multi-function indicator clock switch push button is
used to control the clock/outside temperature display
modes. The multi-function indicator ª+º (plus) and
ª2º (minus) switch push buttons are used to adjust
the cluster general illumination dimming level, the
clock, and other cluster settings. See the owner's
manual in the vehicle glove box for more information
on the features, use, operation and setting proce-
dures for the various standard and optional multi-
function indicator displays.
Proper testing of the multi-function indicator LCD
unit, the CAN data bus and the electronic data bus
message inputs to the instrument cluster that control
some of the multi-function indicator functions
requires the use of a diagnostic scan tool. Refer to
the appropriate diagnostic information. Additional
details for the odometer/trip odometer, the clock, the
gear selector indicator, the ambient temperature indi-
cator and the ASSYST warning and reminder func-
tions of the multi-function indicator may be found
elsewhere in this service information.
ODOMETER
DESCRIPTION
An odometer and trip odometer are standard
equipment in all instrument clusters. The odometer
and trip odometer values are displayed on the left
side of the multi-function indicator Liquid Crystal
Display (LCD). The LCD is soldered onto the cluster
electronic circuit board and is visible through a win-
dow with a clear lens located near the lower edge of
8J - 22 INSTRUMENT CLUSTERVA

received by the cluster from the Engine Control Mod-
ule (ECM) over the Controller Area Network (CAN)
data bus. The tachometer is an air core magnetic
unit that receives battery current on the instrument
cluster electronic circuit board when the instrument
cluster detects that the ignition switch is in the On
position. The cluster is programmed to move the
gauge needle back to the low end of the scale after
the ignition switch is turned to the Off position. The
instrument cluster circuitry controls the gauge nee-
dle position and provides the following features:
²Engine Speed Message- Each time the cluster
receives an engine speed message from the ECM it
will calculate the correct engine speed reading and
position the gauge needle at that relative speed posi-
tion on the gauge scale. The gauge needle will con-
tinually be repositioned at the relative engine speed
position on the gauge scale until the engine stops
running, or until the ignition switch is turned to the
Off position, whichever occurs first.
²Communication Error- If the cluster fails to
receive an engine speed message, it will hold the
gauge needle at the last indication for about three
seconds, or until the ignition switch is turned to the
Off position, whichever occurs first. After three sec-
onds, the gauge needle will return to the left end of
the gauge scale.
The ECM continually monitors the crankshaft posi-
tion sensor to determine the engine speed. The ECM
then sends the proper engine speed messages to the
instrument cluster. For proper diagnosis of the
crankshaft position sensor, the ECM, the CAN data
bus, or the electronic message inputs to the instru-
ment cluster that control the tachometer, a diagnos-
tic scan tool is required. Refer to the appropriate
diagnostic information.
TRACTION CONTROL INDICA-
TOR
DESCRIPTION
A traction control (ASR) indicator is standard
equipment on all instrument clusters. The traction
control indicator is located near the center of the
speedometer in the instrument cluster. The traction
control indicator consists of an ª!º (exclamation point)
imprinted within a triangular cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. An
amber Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the excla-
mation point to appear silhouetted against an amber
field through the translucent outer layer of the over-
lay when the indicator is illuminated from behind by
the LED, which is soldered onto the instrument clus-ter electronic circuit board. The traction control indi-
cator is serviced as a unit with the instrument
cluster.
OPERATION
The traction control (ASR) indicator gives several
indications to the vehicle operator concerning the
operating status of the traction control (ASR) system.
The traction control indicator is controlled by a tran-
sistor on the instrument cluster circuit board based
upon cluster programming and electronic messages
received by the cluster from the Controller Anti-lock
Brake (CAB) over the Controller Area Network
(CAN) data bus. The traction control indicator Light
Emitting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the traction con-
trol indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the traction control indica-
tor is illuminated for about two seconds as a bulb
test.
²Traction Control (ASR) Indicator Lamp-On
Message- Each time the cluster receives a traction
control indicator lamp-on message from the CAB, the
indicator will be illuminated. This indicator can be
flashed on and off, or illuminated solid, as dictated
by the CAB message. The indicator is illuminated
solid when the traction control system has been deac-
tivated; and is flashed when the traction control is
activated or when the driven wheels lose traction
with the traction control deactivated. The indicator
remains flashing or illuminated solid until the clus-
ter receives a lamp-off message from the CAB, or
until the ignition switch is turned to the Off position,
whichever occurs first.
The CAB continually monitors the traction control
(ASR) switch and the four wheel speed sensors to
determine the correct operating mode for the traction
control system. The CAB then sends the proper
lamp-on or lamp-off messages to the instrument clus-
ter. See the owner's manual in the vehicle glove box
for more information on the features, use, activation
and deactivation of the traction control (ASR) system.
For proper diagnosis of the traction control system,
the CAB, the CAN data bus, or the electronic mes-
sage inputs to the instrument cluster that control the
traction control indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
8J - 26 INSTRUMENT CLUSTERVA

TRACTION CONTROL MAL-
FUNCTION INDICATOR
DESCRIPTION
A traction control (ASR) malfunction indicator is
standard equipment on all instrument clusters. The
traction control malfunction indicator is located near
the lower edge of the instrument cluster, to the right
of the multi-function indicator display. The traction
control malfunction indicator consists of an icon that
graphically depicts a tire and two skid marks
imprinted within a rectangular cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. An
amber Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the icon to
appear silhouetted against an amber field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The traction control malfunction
indicator is serviced as a unit with the instrument
cluster.
OPERATION
The traction control (ASR) malfunction indicator
gives the vehicle operator an indication when the
traction control system is faulty or inoperative. This
indicator is controlled by a transistor on the instru-
ment cluster circuit board based upon cluster pro-
gramming and electronic messages received by the
cluster from the Controller Antilock Brake (CAB)
over the Controller Area Network (CAN) data bus.
The traction control malfunction indicator Light
Emitting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the traction con-
trol malfunction indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the traction control indica-
tor is illuminated as a bulb test until the engine is
started.
²Traction Control (ASR) Malfunction Indica-
tor Lamp-On Message- Each time the cluster
receives a traction control malfunction indicator
lamp-on message from the CAB, the indicator will be
illuminated. The indicator remains illuminated until
the cluster receives a lamp-off message from the
CAB, or until the ignition switch is turned to the Off
position, whichever occurs first.The CAB continually monitors the traction control
(ASR) system circuits and sensors to decide whether
the system is in good operating condition. The CAB
then sends the proper lamp-on or lamp-off messages
to the instrument cluster. If the CAB sends a
lamp-on message after the bulb test, it indicates that
the CAB has detected a system malfunction and that
the traction control (ASR) system has become inoper-
ative. The CAB will store a Diagnostic Trouble Code
(DTC) for any malfunction it detects. In addition, if
the traction control malfunction indicator is illumi-
nated, the CAB will deactivate an activated traction
control system and engine power output may be
reduced. See the owner's manual in the vehicle glove
box for more information on the features, use, activa-
tion and deactivation of the traction control (ASR)
system. For proper diagnosis of the traction control
system, the CAB, the CAN data bus, or the electronic
message inputs to the instrument cluster that control
the traction control malfunction indicator, a diagnos-
tic scan tool is required. Refer to the appropriate
diagnostic information.
TURN SIGNAL INDICATOR
DESCRIPTION
Two turn signal indicators, one right and one left,
are standard equipment on all instrument clusters.
The turn signal indicators are located near the upper
edge of the instrument cluster, one to each side of the
speedometer. Each turn signal indicator consists of a
arrow-shaped cutout of the International Control and
Display Symbol icon for ªTurn Warningº in the
opaque layer of the instrument cluster overlay. The
dark outer layer of the overlay prevents these icons
from being clearly visible when they are not illumi-
nated. A green Light Emitting Diode (LED) behind
each turn signal indicator cutout in the opaque layer
of the overlay causes the icon to appear in green
through the translucent outer layer of the overlay
when the indicator is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. The turn signal indicators
are serviced as a unit with the instrument cluster.
OPERATION
The turn signal indicators give an indication to the
vehicle operator that the turn signal (left or right
indicator flashing) or hazard warning (both left and
right indicators flashing) have been selected and are
operating. These indicators are controlled by transis-
tors on the instrument cluster electronic circuit board
based upon the cluster programming and a hard
wired input received by the cluster from the turn sig-
nal relay through the turn signal and hazard warn-
ing switch circuitry of the multi-function switch on
VAINSTRUMENT CLUSTER 8J - 27