odometer JEEP LIBERTY 2002 KJ / 1.G User Guide

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OPERATION
The cruise indicator gives an indication to the vehi-
cle operator when the speed control system is turned
On, regardless of whether the speed control is
engaged. This indicator is controlled by a transistor
on the instrument cluster electronic circuit board
based upon the cluster programming and electronic
messages received by the cluster from the Powertrain
Control Module (PCM) over the Programmable Com-
munications Interface (PCI) data bus. The cruise
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 receives a battery cur-
rent input on the fused ignition switch output (run-
start) circuit. Therefore, the LED will always be off
when the ignition switch is in any position except On
or Start. The LED only illuminates when it is pro-
vided a path to ground by the instrument cluster
transistor. The instrument cluster will turn on the
cruise indicator for the following reasons:
²Cruise Lamp-On Message- Each time the
cluster receives a cruise lamp-on message from the
PCM indicating the speed control system has been
turned On, the cruise indicator is illuminated. The
indicator remains illuminated until the cluster
receives a cruise lamp-off message from the PCM or
until the ignition switch is turned to the Off position,
whichever occurs first.
²Actuator Test- Each time the cluster is put
through the actuator test, the cruise indicator will be
turned on, then off again during the bulb check por-
tion of the test in order to confirm the functionality
of the LED and the cluster control circuitry.
The PCM continually monitors the speed control
switches to determine the proper outputs to the
speed control servo. The PCM then sends the proper
cruise indicator lamp-on and lamp-off messages to
the instrument cluster. For further diagnosis of the
cruise indicator or the instrument cluster circuitry
that controls the indicator, (Refer to 8 - ELECTRI-
CAL/INSTRUMENT CLUSTER - DIAGNOSIS AND
TESTING). For proper diagnosis of the speed control
system, the PCM, the PCI data bus, or the electronic
message inputs to the instrument cluster that control
the cruise indicator, a DRBIIItscan tool is required.
Refer to the appropriate diagnostic information.
DOOR AJAR INDICATOR
DESCRIPTION
A door ajar indicator is standard equipment on all
instrument clusters. The door ajar indicator consists
of the word ªdoorº, which appears in place of the
odometer/trip odometer information in the Vacuum-Fluorescent Display (VFD) of the instrument cluster.
The VFD is part of the cluster electronic circuit
board, and is visible through a cutout located near
the lower edge of the speedometer dial face in the
instrument cluster. The dark outer layer of the over-
lay prevents the VFD from being clearly visible when
it is not illuminated. The word ªdoorº appears in the
same blue-green color and at the same lighting level
as the odometer/trip odometer information through
the translucent outer layer of the overlay when it is
illuminated by the instrument cluster electronic cir-
cuit board. The door ajar indicator is serviced as a
unit with the instrument cluster.
OPERATION
The door ajar indicator gives an indication to the
vehicle operator that one or more of the passenger
compartment doors may be open or not completely
latched. This indicator is controlled by the instru-
ment cluster electronic circuit board based upon clus-
ter programming and electronic messages received by
the cluster from the Body Control Module (BCM)
over the Programmable Communications Interface
(PCI) data bus. The door ajar indicator function of
the Vacuum Fluorescent Display (VFD) is completely
controlled by the instrument cluster logic circuit, and
that logic will only allow this indicator to operate
when the instrument cluster receives a battery cur-
rent input on the fused ignition switch output (run-
start) circuit. Therefore, the VFD door ajar indication
will always be off when the ignition switch is in any
position except On or Start. The instrument cluster
will turn on the door ajar indicator for the following
reasons:
²Door Ajar Lamp-On Message- Each time the
cluster receives a door ajar lamp-on message from
the BCM indicating that a door is open or not com-
pletely latched, the door ajar indicator will be illumi-
nated. If the vehicle is not moving when the door
ajar lamp-on message is received, the VFD will
repeatedly and sequentially cycle its indication in
two second intervals with the odometer/trip odometer
information, the door ajar warning, and any other
active warnings including: gate ajar, glass ajar, and
low washer fluid. If the vehicle is moving, or once the
cluster of a non-moving vehicle receives an electronic
vehicle speed message from the Powertrain Control
Module (PCM) indicating a speed greater than zero,
the warning sequence will consist of three complete
display cycles, then revert to only the odometer/trip
odometer display until the door ajar switch is cycled.
The door ajar indicator will also be extinguished
when the cluster receives a door ajar lamp-off mes-
sage from the BCM, or if the ignition switch is
turned to the Off position, whichever occurs first.
KJINSTRUMENT CLUSTER 8J - 17
CRUISE INDICATOR (Continued)

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OPERATION
The fuel gauge gives an indication to the vehicle
operator of the level of fuel in the fuel tank. This
gauge is controlled by the instrument cluster circuit
board based upon cluster programming and elec-
tronic messages received by the cluster from the
Powertrain Control Module (PCM) over the Program-
mable Communications Interface (PCI) data bus. The
fuel gauge is an air core magnetic unit that receives
battery current on the instrument cluster electronic
circuit board through the fused ignition switch out-
put (run-start) circuit whenever the ignition switch is
in the On or Start positions. The cluster is pro-
grammed 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:
²Percent Tank Full Message- Each time the
cluster receives a message from the PCM indicating
the percent tank full, the cluster moves the gauge
needle to the relative fuel level position on the gauge
scale. The PCM applies an algorithm to the input
from the fuel tank sender to dampen gauge needle
movement against the negative effect that fuel slosh-
ing within the fuel tank can have on accurate inputs
to the PCM.
²Less Than 12.5 Percent Tank Full Message-
Each time the cluster receives messages from the
PCM indicating the percent tank full is less than
12.5 (one-eighth), the gauge needle is moved to the
proper position on the gauge scale and the low fuel
indicator is illuminated. The low fuel indicator
remains illuminated until the cluster receives mes-
sages from the PCM indicating that the percent tank
full is greater than 12.5 (one-eighth), or until the
ignition switch is turned to the Off position, which-
ever occurs first.
²Less Than Empty Percent Tank Full Mes-
sage- Each time the cluster receives a message from
the PCM indicating the percent tank full is less than
empty, the gauge needle is moved to the far left (low)
end of the gauge scale and the low fuel indicator is
illuminated immediately. This message would indi-
cate that the fuel tank sender input to the PCM is a
short circuit.
²More Than Full Percent Tank Full Message
- Each time the cluster receives a message from the
PCM indicating the percent tank full is more than
full, the gauge needle is moved to the far left (low)
end of the gauge scale and the low fuel indicator is
illuminated immediately. This message would indi-
cate that the fuel tank sender input to the PCM is an
open circuit.
²Actuator Test- Each time the cluster is put
through the actuator test, the gauge needle will beswept to the gauge calibration points on the gauge
scale in sequence in order to confirm the functional-
ity of the gauge and the cluster control circuitry.
The PCM continually monitors the fuel tank
sender input to determine the fuel level. The PCM
then applies an algorithm to the input and sends the
proper percent tank full messages to the instrument
cluster. For further diagnosis of the fuel gauge or the
instrument cluster circuitry that controls the gauge,
(Refer to 8 - ELECTRICAL/INSTRUMENT CLUS-
TER - DIAGNOSIS AND TESTING). For proper
diagnosis of the fuel tank sender, the PCM, the PCI
data bus, or the electronic message inputs to the
instrument cluster that control the fuel gauge, a
DRBIIItscan tool is required. Refer to the appropri-
ate diagnostic information.
GATE AJAR INDICATOR
DESCRIPTION
A gate ajar indicator is standard equipment on all
instrument clusters. The gate ajar indicator consists
of the word ªgateº, which appears in place of the
odometer/trip odometer information in the Vacuum-
Fluorescent Display (VFD) of the instrument cluster.
The VFD is part of the cluster electronic circuit
board, and is visible through a cutout located near
the lower edge of the speedometer dial face in the
instrument cluster. The dark outer layer of the over-
lay prevents the VFD from being clearly visible when
it is not illuminated. The word ªgateº appears in the
same blue-green color and at the same lighting level
as the odometer/trip odometer information through
the translucent outer layer of the overlay when it is
illuminated by the instrument cluster electronic cir-
cuit board. The gate ajar indicator is serviced as a
unit with the instrument cluster.
OPERATION
The gate ajar indicator gives an indication to the
vehicle operator that the rear tailgate may be open
or not completely latched. This indicator is controlled
by the instrument cluster electronic circuit board
based upon cluster programming and electronic mes-
sages received by the cluster from the Body Control
Module (BCM) over the Programmable Communica-
tions Interface (PCI) data bus. The gate ajar indica-
tor function of the Vacuum Fluorescent Display
(VFD) is completely controlled by the instrument
cluster logic circuit, and that logic will only allow
this indicator to operate when the instrument cluster
receives a battery current input on the fused ignition
switch output (run-start) circuit. Therefore, the VFD
gate ajar indicator will always be off when the igni-
tion switch is in any position except On or Start. The
8J - 20 INSTRUMENT CLUSTERKJ
FUEL GAUGE (Continued)

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instrument cluster will turn on the gate ajar indica-
tor for the following reasons:
²Gate Ajar Lamp-On Message- Each time the
cluster receives a gate ajar lamp-on message from
the BCM indicating that the rear tailgate is open or
not completely latched, the gate ajar indicator will be
illuminated. If the vehicle is not moving when the
gate ajar lamp-on message is received, the VFD will
repeatedly and sequentially cycle its indication in
two second intervals with the odometer/trip odometer
information, the gate ajar warning, and any other
active warnings including: door ajar, glass ajar, and
low washer fluid. If the vehicle is moving, or once the
cluster of a non-moving vehicle receives an electronic
vehicle speed message from the Powertrain Control
Module (PCM) indicating a speed greater than zero,
the warning sequence will consist of three complete
display cycles, then revert to only the odometer/trip
odometer display until the tailgate ajar switch is
cycled. The gate ajar indicator will also be extin-
guished when the cluster receives a gate ajar lamp-
off message from the BCM, or if the ignition switch is
turned to the Off position, whichever occurs first.
The BCM continually monitors the tailgate ajar
switch that is integral to the tailgate latch to deter-
mine the status of the rear tailgate. The BCM then
sends the proper gate ajar lamp-on and lamp-off mes-
sages to the instrument cluster. For further diagnosis
of the gate ajar indicator or the instrument cluster
circuitry that controls the indicator, (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER - DIAGNO-
SIS AND TESTING). For proper diagnosis of the tail-
gate ajar switch and circuit, the BCM, the PCI data
bus, or the electronic message inputs to the instru-
ment cluster that control the gate ajar indicator, a
DRBIIItscan tool is required. Refer to the appropri-
ate diagnostic information.
GLASS AJAR INDICATOR
DESCRIPTION
A glass ajar indicator is standard equipment on all
instrument clusters. The glass ajar indicator consists
of the word ªglassº, which appears in place of the
odometer/trip odometer information in the Vacuum-
Fluorescent Display (VFD) of the instrument cluster.
The VFD is part of the cluster electronic circuit
board, and is visible through a cutout located near
the lower edge of the speedometer dial face in the
instrument cluster. The dark outer layer of the over-
lay prevents the VFD from being clearly visible when
it is not illuminated. The word ªglassº appears in the
same blue-green color and at the same lighting level
as the odometer/trip odometer information through
the translucent outer layer of the overlay when it isilluminated by the instrument cluster electronic cir-
cuit board. The glass ajar indicator is serviced as a
unit with the instrument cluster.
OPERATION
The glass ajar indicator gives an indication to the
vehicle operator that the rear flip-up glass may be
open or not completely latched. This indicator is con-
trolled by the instrument cluster electronic circuit
board based upon cluster programming and elec-
tronic messages received by the cluster from the
Body Control Module (BCM) over the Programmable
Communications Interface (PCI) data bus. The glass
ajar indicator function of the Vacuum Fluorescent
Display (VFD) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster receives a battery current input on the fused
ignition switch output (run-start) circuit. Therefore,
the VFD glass ajar indicator will always be off when
the ignition switch is in any position except On or
Start. The instrument cluster will turn on the glass
ajar indicator for the following reasons:
²Glass Ajar Lamp-On Message- Each time the
cluster receives a glass ajar lamp-on message from
the BCM indicating that the rear flip-up glass is
open or not completely latched, the glass ajar indica-
tor will be illuminated. If the vehicle is not moving
when the glass ajar lamp-on message is received, the
VFD will repeatedly and sequentially cycle its indica-
tion in two second intervals with the odometer/trip
odometer information, the glass ajar warning, and
any other active warnings including: door ajar, gate
ajar, and low washer fluid. If the vehicle is moving,
or once the cluster of a non-moving vehicle receives
an electronic vehicle speed message from the Power-
train Control Module (PCM) indicating a speed
greater than zero, the warning sequence will consist
of three complete display cycles, then revert to only
the odometer/trip odometer display until the glass
ajar switch is cycled. The glass ajar indicator will
also be extinguished when the cluster receives a
glass ajar lamp-off message from the BCM, or if the
ignition switch is turned to the Off position, which-
ever occurs first.
The BCM continually monitors the glass ajar
switch that is integral to the flip-up glass latch to
determine the status of the rear flip-up glass. The
BCM then sends the proper glass ajar lamp-on and
lamp-off messages to the instrument cluster. For fur-
ther diagnosis of the glass ajar indicator or the
instrument cluster circuitry that controls the indica-
tor, (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). For
proper diagnosis of the glass ajar switch and circuit,
the BCM, the PCI data bus, or the electronic mes-
KJINSTRUMENT CLUSTER 8J - 21
GATE AJAR INDICATOR (Continued)

Page 428 of 1803

dition. The PCM then sends the proper malfunction
indicator lamp-on or lamp-off messages to the instru-
ment cluster. For further diagnosis of the MIL or the
instrument cluster circuitry that controls the LED,
(Refer to 8 - ELECTRICAL/INSTRUMENT CLUS-
TER - DIAGNOSIS AND TESTING). If the instru-
ment cluster turns on the MIL after the bulb test, it
may indicate that a malfunction has occurred and
that the fuel and emissions system may require ser-
vice. For proper diagnosis of the fuel and emissions
systems, the PCM, the PCI data bus, or the elec-
tronic message inputs to the instrument cluster that
control the MIL, a DRBIIItscan tool is required.
Refer to the appropriate diagnostic information.
ODOMETER
DESCRIPTION
An odometer and trip odometer are standard
equipment in all instrument clusters. The odometer
and trip odometer information are displayed in a
common electronic, blue-green Vacuum Fluorescent
Display (VFD), which is located in the lower edge of
the speedometer dial face in the instrument cluster
and, when illuminated, is visible through a small
window cutout in the cluster overlay. However, the
odometer and trip odometer information are not dis-
played simultaneously. The trip odometer reset
switch on the instrument cluster electronic circuit
board toggles the display between odometer and trip
odometer modes by depressing the odometer/trip
odometer switch knob that extends through the lower
edge of the cluster lens, just right of the odometer
VFD. Both the odometer and trip odometer informa-
tion is stored in the instrument cluster memory.
All odometer and trip odometer distance informa-
tion is stored in the instrument cluster. This distance
information can be increased when the proper inputs
are provided to the instrument cluster, but the dis-
tance information cannot be decreased. The odometer
can display values up to 864,004 kilometers (536,870
miles). The odometer will not roll over, but will latch
at the maximum value. The trip odometer can dis-
play values up to 9999.9 kilometers (9999.9 miles)
before it rolls over to zero. The odometer display does
not have a decimal point and will not show values
less than a full unit (kilometer or mile), the trip
odometer display does have a decimal point and will
show tenths of a unit (kilometer or mile). When the
trip odometer is active, the word ªTRIPº will also
illuminate near the bottom of the VFD. The unit of
measure for the odometer and trip odometer display
is not shown in the VFD. If the instrument cluster
has a kilometers-per-hour primary speedometer
scale, the odometer/trip odometer registers kilome-ters; and if the cluster features a miles-per-hour pri-
mary speedometer scale, the odometer/trip odometer
registers miles. In this instrument cluster, the odom-
eter/trip odometer VFD is also used to display certain
warning messages and diagnostic information.
The odometer/trip odometer has a ªRental Carº
mode, which will illuminate the odometer informa-
tion in the VFD whenever the driver side front door
is opened with the ignition switch in the Off or
Accessory positions. During daylight hours (exterior
lamps Off) the VFD is illuminated at full brightness
for clear visibility. At night (exterior lamps are On)
the instrument cluster converts an electronic dim-
ming level message received from the Body Control
Module (BCM) over the Programmable Communica-
tions Interface (PCI) data bus to a digital dimming
level signal for controlling the lighting level of the
VFD. However, a ªParadeº mode position of the panel
lamps dimmer control ring on the multi-function
switch left control stalk allows the VFD to be illumi-
nated at full brightness if the exterior lamps are
turned On during daylight hours.
The VFD, the trip odometer switch, and the trip
odometer switch button are serviced as a unit with
the instrument cluster.
OPERATION
The odometer and trip odometer give an indication
to the vehicle operator of the distance the vehicle has
traveled. This gauge is controlled by the instrument
cluster electronic circuitry based upon cluster pro-
gramming and electronic messages received by the
cluster from the Powertrain Control Module (PCM)
over the Programmable Communications Interface
(PCI) data bus. The odometer and trip odometer
information is displayed by the instrument cluster
Vacuum Fluorescent Display (VFD). The VFD will
display the odometer information whenever the
driver side front door is opened with the ignition
switch in the Off or Accessory positions, and will dis-
play the last previously selected odometer or trip
odometer information when the ignition switch is in
the On or Start positions. The instrument cluster cir-
cuitry controls the VFD and provides the following
features:
²Odometer/Trip Odometer Display Toggling-
Actuating the trip odometer reset switch momen-
tarily with the VFD illuminated will toggle the dis-
play between the odometer and trip odometer
information. Each time the VFD is illuminated with
the ignition switch in the On or Start positions, the
display will automatically return to the last mode
previously selected (odometer or trip odometer).
²Trip Odometer Reset- When the trip odome-
ter reset switch is pressed and held for longer than
about two seconds with the ignitions switch in the
KJINSTRUMENT CLUSTER 8J - 25
MALFUNCTION INDICATOR LAMP (MIL) (Continued)

Page 429 of 1803

On or Start positions, the trip odometer will be reset
to 0.0 kilometers (miles). The VFD must be display-
ing the trip odometer information in order for the
trip odometer information to be reset.
²Warning Display- The odometer or trip odom-
eter information will be toggled at two second inter-
vals with a warning display when certain monitored
conditions are active. If multiple conditions are
active, the VFD will toggle each active warning and
the odometer/trip odometer information at two sec-
ond intervals. Once the vehicle is moving and a vehi-
cle speed input is received by the instrument cluster,
each active warning will be displayed for three two-
second intervals before the VFD reverts to displaying
only the selected odometer or trip odometer informa-
tion. The warnings and monitored conditions include:
²ªdoorº- A door is open or not fully latched.
²ªgateº- The tailgate is open or not fully
latched.
²ªglassº- The rear flip-up glass is open or not
fully latched.
²ªlowashº- The fluid level in the washer reser-
voir is low.
²ªno busº- The instrument cluster can detect no
PCI bus communication. This message is illuminated
solid when there is no PCI bus communication, and
will override the display of all other active warning
displays.
²Communication Error- If the cluster fails to
receive a distance message during normal operation,
it will hold and display the last data received until
the ignition switch is turned to the Off position. If
the cluster does not receive a distance message
within one second after the ignition switch is turned
to the On position, it will display the last distance
message stored in the cluster memory. If the cluster
is unable to display distance information due to an
error internal to the cluster, ªerrorº will be displayed
in the VFD.
²Actuator Test- Each time the cluster is put
through the actuator test, the VFD will step sequen-
tially through a display of ª111111 ºthrough ª999999º,
then display the cluster software version number to
confirm the functionality of the VFD and the cluster
control circuitry.
The PCM continually monitors the vehicle speed
pulse information received from the Body Control
Module (BCM), then sends the proper distance mes-
sages to the instrument cluster. For further diagnosis
of the odometer/trip odometer or the instrument clus-
ter circuitry that controls these functions, (Refer to 8
- ELECTRICAL/INSTRUMENT CLUSTER - DIAG-
NOSIS AND TESTING). For proper diagnosis of the
vehicle speed sensor, the BCM, the PCM, the PCI
data bus, or the electronic message inputs to the
instrument cluster that control the odometer/tripodometer, a DRBIIItscan tool is required. Refer to
the appropriate diagnostic information.
OVERDRIVE OFF INDICATOR
DESCRIPTION
An overdrive off indicator is standard equipment
on all instrument clusters, but is only functional on
vehicles equipped with the optional overdrive auto-
matic transmission. The overdrive off indicator is
located above the fuel gauge and to the left of the
tachometer in the instrument cluster. The overdrive
off indicator consists of a stencil-like cutout of the
text ªO/D OFFº 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 ªO/D OFFº text to appear in
amber through the translucent outer layer of the
overlay when it is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. When the exterior lighting is
turned On, the illumination intensity of the overdrive
off indicator is dimmable, which is adjusted using the
panel lamps dimmer control ring on the left control
stalk of the multi-function switch. The overdrive off
indicator is serviced as a unit with the instrument
cluster.
OPERATION
The overdrive off indicator gives an indication to
the vehicle operator when the Off position of the
overdrive off switch has been selected, disabling the
electronically controlled overdrive feature of the auto-
matic transmission. This indicator is controlled by a
transistor on the instrument cluster electronic circuit
board based upon the cluster programming and elec-
tronic messages received by the cluster from the
Powertrain Control Module (PCM) over the Program-
mable Communications Interface (PCI) data bus. The
overdrive off 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 receives a bat-
tery current input on the fused ignition switch out-
put (run-start) circuit. Therefore, the LED will
always be off when the ignition switch is in any posi-
tion except On or Start. 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 overdrive off indicator for the following
reasons:
²Overdrive Off Lamp-On Message- Each time
the cluster receives an overdrive off lamp-on message
8J - 26 INSTRUMENT CLUSTERKJ
ODOMETER (Continued)

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The turn signal indicators are connected in parallel
with the other turn signal circuits. This arrangement
allows the turn signal indicators to remain func-
tional, regardless of the condition of the other cir-
cuits in the turn signal and hazard warning systems.
The combination flasher outputs of the hazard switch
to the instrument cluster turn signal indicator inputs
can be diagnosed using conventional diagnostic tools
and methods. (Refer to 8 - ELECTRICAL/LAMPS/
LIGHTING - EXTERIOR/HAZARD SWITCH -
DESCRIPTION) for more information on the combi-
nation flasher and hazard switch operation.
WAIT-TO-START INDICATOR
DESCRIPTION
A wait-to-start indicator is only found in the
instrument clusters of vehicles equipped with an
optional diesel engine. The wait-to-start indicator is
located above the fuel gauge and to the left of the
tachometer in the instrument cluster. The wait-to-
start indicator consists of a stencil-like cutout of the
International Control and Display Symbol icon for
ªDiesel Preheatº 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
in amber through the translucent outer layer of the
overlay when it is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. The wait-to-start indicator is
serviced as a unit with the instrument cluster.
OPERATION
The wait-to-start indicator gives an indication to
the vehicle operator when the diesel engine glow
plugs are energized in their pre-heat operating mode.
This indicator is controlled by a transistor on the
instrument cluster electronic circuit board based
upon the cluster programming and electronic mes-
sages received by the cluster from the Powertrain
Control Module (PCM) over the Programmable Com-
munications Interface (PCI) data bus. The wait-to-
start 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 receives a bat-
tery current input on the fused ignition switch out-
put (run-start) circuit. Therefore, the LED will
always be off when the ignition switch is in any posi-
tion except On or Start. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster willturn on the wait-to-start indicator for the following
reasons:
²Wait-To-Start Lamp-On Message- Each time
the cluster receives a wait-to-start lamp-on message
from the PCM indicating the glow plugs are heating
and the driver must wait to start the engine, the
wait-to-start indicator will be illuminated. The indi-
cator remains illuminated until the cluster receives a
wait-to-start lamp-off message, or until the ignition
switch is turned to the Off position, whichever occurs
first.
²Actuator Test- Each time the cluster is put
through the actuator test, the wait-to-start indicator
will be turned on, then off again during the bulb
check portion of the test to confirm the functionality
of the LED and the cluster control circuitry.
The PCM continually monitors the ambient tem-
perature and the glow plug pre-heater circuits to
determine how long the glow plugs must be heated in
the pre-heat operating mode. The PCM then sends
the proper wait-to-start lamp-on and lamp-off mes-
sages to the instrument cluster. For further diagnosis
of the wait-to-start indicator or the instrument clus-
ter circuitry that controls the indicator, (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER - DIAGNO-
SIS AND TESTING). For proper diagnosis of the
glow plug pre-heater control circuits, the PCM, the
PCI data bus, or the electronic message inputs to the
instrument cluster that control the wait-to-start indi-
cator, a DRBIIItscan tool is required. Refer to the
appropriate diagnostic information.
WASHER FLUID INDICATOR
DESCRIPTION
A washer fluid indicator is standard equipment on
all instrument clusters. The washer fluid indicator
consists of the text ªlowashº, which appears in place
of the odometer/trip odometer information in the Vac-
uum-Fluorescent Display (VFD) of the instrument
cluster. The VFD is part of the cluster electronic cir-
cuit board, and is visible through a cutout located
near the lower edge of the speedometer dial face in
the instrument cluster. The dark outer layer of the
overlay prevents the VFD from being clearly visible
when it is not illuminated. The text message
ªlowashº appears in the same blue-green color and at
the same lighting level as the odometer/trip odometer
information through the translucent outer layer of
the overlay when it is illuminated by the instrument
cluster electronic circuit board. The washer fluid
indicator is serviced as a unit with the instrument
cluster.
KJINSTRUMENT CLUSTER 8J - 35
TURN SIGNAL INDICATOR (Continued)

Page 439 of 1803

OPERATION
The washer fluid indicator gives an indication to
the vehicle operator that the fluid level in the washer
reservoir is low. This indicator is controlled by the
instrument cluster electronic circuit board based
upon cluster programming and a hard wired input
received by the cluster from the washer fluid level
switch mounted on the washer reservoir. The washer
fluid indicator function of the Vacuum Fluorescent
Display (VFD) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster receives a battery current input on the fused
ignition switch output (run-start) circuit. Therefore,
the LED will always be off when the ignition switch
is in any position except On or Start. The instrument
cluster will turn on the washer fluid indicator for the
following reasons:
²Washer Fluid Level Switch Input- Each time
the cluster detects ground on the low washer fluid
sense circuit (washer fluid level switch closed =
washer fluid level low) the cluster applies an algo-
rithm to confirm that the input is correct and not the
result of fluid sloshing in the washer reservoir. The
cluster tests the status of the circuit about seven mil-
liseconds after ignition On, and about once every sec-
ond thereafter, then uses an internal counter to
count up or down. When the counter accumulates
thirty ground inputs on the circuit, the washer fluid
indicator will be illuminated. If the vehicle is not
moving when the washer fluid level switch input
counter reaches thirty, the VFD will repeatedly and
sequentially cycle its indication in two second inter-
vals with the odometer/trip odometer information,
the low washer fluid warning, and any other active
warnings including: door ajar, gate ajar, and glass
ajar. If the vehicle is moving, or once the cluster of a
non-moving vehicle receives an electronic vehicle
speed message from the Powertrain Control Module
(PCM) indicating a speed greater than zero, the
warning sequence will consist of three complete dis-
play cycles, then revert to only the odometer/trip
odometer display. Once the washer fluid indicator
warning has completed, the washer fluid indicator is
extinguished and will not repeat until the ignition
switch is cycled.
The instrument cluster continually monitors the
washer fluid level switch in the washer reservoir to
determine the status of the washer fluid level. For
further diagnosis of the washer fluid indicator or the
instrument cluster circuitry that controls the indica-
tor, (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). The
washer fluid level switch and circuits can be diag-
nosed using conventional diagnostic tools and meth-
ods. The washer fluid level switch also features a 3.3kilohm diagnostic resistor connected in parallel
between the switch input and output to provide the
cluster with verification that the low washer fluid
sense circuit is not open or shorted. This input can
be monitored using a DRBIIItscan tool. Refer to the
appropriate diagnostic information.
DIAGNOSIS AND TESTING - WASHER FLUID
INDICATOR
The diagnosis found here addresses an inoperative
washer fluid indicator condition. If the problem being
diagnosed is related to indicator accuracy, be certain
to confirm that the problem is with the indicator or
washer fluid level switch input and not with a dam-
aged or empty washer fluid reservoir, or inoperative
instrument cluster indicator control circuitry. Inspect
the washer fluid reservoir for proper fluid level and
signs of damage or distortion that could affect
washer fluid level switch performance and perform
the instrument cluster actuator test before you pro-
ceed with the following diagnosis. If no washer fluid
reservoir or instrument cluster control circuitry prob-
lem is found, the following procedure will help to
locate a short or open in the washer fluid switch
sense circuit. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
details of wire harness routing and retention, connec-
tor pin-out information and location views for the
various wire harness connectors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
INDICATOR DOES NOT ILLUMINATE WITH WASHER
RESERVOIR EMPTY
(1) Disconnect and isolate the battery negative
cable. Disconnect the headlamp and dash wire har-
ness connector for the washer fluid level switch from
the washer fluid level switch connector receptacle.
Check for continuity between the ground circuit cav-
8J - 36 INSTRUMENT CLUSTERKJ
WASHER FLUID INDICATOR (Continued)

Page 598 of 1803

The CMTC may also be integrated with the Uni-
versal Transmitter. If so, your CMTC module will
have three buttons centered together between the
outer four buttons. Below the three buttons are cor-
responding dots to indicate which button you are
using.
The Compass Mini-Trip Computer includes the fol-
lowing display options:
²Compass and thermometer- provides the out-
side temperature and one of eight compass readings
to indicate the direction the vehicle is facing.
²Average fuel economy- shows the average
fuel economy since the last trip computer reset.
²Distance to empty- shows the estimated dis-
tance that can be travelled with the fuel remaining
in the fuel tank. This estimated distance is computed
using the average miles-per-gallon from the last 30
gallons of fuel used.
²Instant fuel economy- shows the present fuel
economy based upon the current vehicle distance and
fuel used information.
²Trip odometer- shows the distance travelled
since the last trip computer reset.
²Elapsed time- shows the accumulated igni-
tion-on time since the last trip computer reset.
²Blank screen- the CMTC compass/thermome-
ter/trip computer VFD is turned off.
If the vehicle is equipped with the optional Univer-
sal Transmitter transceiver, the CMTC will also dis-
play messages and an icon indicating when the
Universal Transmitter is being trained, which of the
three transmitter buttons is transmitting, and when
the transceiver is cleared.
Data input for all CMTC functions, including VFD
dimming level, is received through PCI data bus
messages. The CMTC module uses its internal pro-
gramming and all of its data inputs to calculate and
display the requested data. If the data displayed is
incorrect, perform the self-diagnostic tests as
described in this group. If these tests prove inconclu-
sive, the use of a DRBIIItscan tool and the proper
Diagnostic Procedures manual are recommended for
further testing of the CMTC module and the PCI
data bus.
The CMTC module cannot be repaired, and is
available for service only as a unit. This unit
includes the push button switches and the plastic
module and display lens. If any of these components
is faulty or damaged, the complete CMTC module
must be replaced. The incandescent bulbs used for
CMTC push button back-lighting are available for
service replacement.
DESCRIPTION - COMPASS
While in the compass/thermometer mode, the com-
pass will display the direction in which the vehicle ispointed using the eight major compass headings
(Examples: north is N, northeast is NE). The self-cal-
ibrating compass unit requires no adjusting in nor-
mal use. The only calibration that may prove
necessary is to drive the vehicle in three complete
circles at 5 to 8 kilometers-per-hour (3 to 5 miles-per-
hour), on level ground, in not less than forty-eight
seconds. This will reorient the compass unit to its
vehicle.
The compass unit also will compensate for magne-
tism the body of the vehicle may acquire during nor-
mal use. However, avoid placing anything magnetic
directly on the roof of the vehicle. Magnetic mounts
for an antenna, a repair order hat, or a funeral pro-
cession flag can exceed the compensating ability of
the compass unit if placed on the roof panel. Mag-
netic bit drivers used on the fasteners that hold the
overhead console assembly to the roof header can
also affect compass operation. If the vehicle roof
should become magnetized, the demagnetizing and
calibration procedures found in this group may be
required to restore proper compass operation.
DESCRIPTION - THERMOMETER
The thermometer displays the outside ambient
temperature in whole degrees. The temperature dis-
play can be toggled from Fahrenheit to Celsius by
using the U.S./Metric button. The displayed temper-
ature is not an instant reading of conditions, but an
average temperature. It may take the thermometer
display several minutes to respond to a major tem-
perature change, such as driving out of a heated
garage into winter temperatures.
When the ignition switch is turned to the Off posi-
tion, the last displayed temperature reading stays in
the Body Control Module (BCM) unit memory. When
the ignition switch is turned to the On position
again, the CMTC will display the memory tempera-
ture for one minute; then update the display to the
current average temperature reading within five
minutes.
The thermometer function is supported by an
ambient temperature sensor. The sensor is mounted
outside the passenger compartment near the front
and center of the vehicle, and is hard wired to the
Body Control Module (BCM). The BCM sends tem-
perature status messages to the CMTC module over
the PCI data bus network. The ambient temperature
sensor is available as a separate service item, refer to
additional information later in this section.
OPERATION
The compass mini-trip computer operates when the
ignition is in the ON position. The VFD will display
the last display before ignition was turned OFF. The
four outer buttons operate:
KJMESSAGE SYSTEMS 8M - 5
COMPASS/MINI-TRIP COMPUTER (Continued)

Page 599 of 1803

²STEP
²C/T - Compass/Temperature
²US/M - English/Metric
²RESET
1. STEP BUTTON
Pressing the STEP button selects one of the follow-
ing 6 displays:
²Average fuel economy
²Distance to empty
²Instantaneous fuel economy
²Trip odometer
²Elapsed time
²Blank Screen
2. C/T (COMPASS/TEMPERATURE)
BUTTON
Pressing the C/T button selects the Compass/Tem-
perature display.
3. US/M (ENGLISH/METRIC
MEASUREMENT) BUTTON
Pressing the US/M button switches the display
units between English and Metric readings.
4. RESET BUTTON
Pressing the RESET button resets the function on
the display, provided that function can be reset. The
functions which can be reset are Average fuel econ-
omy, Trip odometer and Elapsed time.
Global ResetThis feature allows all three dis-
plays (Average fuel economy, Trip odometer and
Elapsed time) to be reset easily, by pressing the
RESET button twice within three seconds with any
of the screens in display. This eliminates the need to
reset each display individually.
The RESET button is also used to set the variance
and/or calibrate the compass. Refer to the Variance
Procedure and Calibration Procedure in this section.
For more information on the features, control func-
tions and setting procedures for the CMTC module,
see the owner's manual in the vehicle glove box.
DIAGNOSIS AND TESTING - COMPASS
MINI-TRIP COMPUTER
The following diagnostic procedure can be used if
the compass mini-trip computer is not operational in
any way. If the problem is specific to a individual
CMTC display, go to the appropriate display title
noted below and diagnose using the information pro-
vided on how these displays are generated.
(1) Remove the overhead console from the head-
liner (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - REMOVAL).
(2) Using a ohmmeter, check the ground circuit
cavity of the compass mini-trip computer electricalconnector for proper continuity to ground. Continuity
should be present, If OK go to Step 3, If not OK
repair the open or shorted ground circuit as required.
NOTE: Connect the negative battery cable before
proceeding.
(3) Using a voltmeter, check the fused (B+) circuit
cavity of the compass mini-trip computer electrical
connector for 12v. Voltage should be present, If OK go
to Step 4, If not OK repair the open or shorted fused
(B+) circuit as required.
(4) Using a voltmeter, check the fused ignition
switch output circuit cavity of the compass mini-trip
computer electrical connector for 12v with Key ON.
Voltage should be present, If OK, replace the inoper-
ative CMTC module, If not OK repair the open or
shorted fused ignition switch output circuit as
required.
TEMPERATURE
The compass mini-trip computer receives Program-
mable Communications Interface bus (PCI bus) mes-
sages from the Body Control Module (BCM) for all
displayed information except the compass display. If
a dash (-) is displayed, the compass mini-trip com-
puter is not receiving a PCI bus message from the
BCM. To check out the PCI bus line and the BCM,
use the DRB llltscan tool and proper Body Diagnos-
tic Procedure Manual.
If the compass mini-trip computer displays a tem-
perature more than 54É C (130É F), check for a short
circuit between the temperature sensor and the
BCM.
If the compass mini-trip computer displays a tem-
perature less than -40É C (-67É F), check for an open
circuit between the temperature sensor and the
BCM.
AVERAGE FUEL ECONOMY
The compass mini-trip computer receives average
fuel economy information from the BCM over the PCI
bus line. If the compass mini-trip computer displays
-.- instead of an average fuel economy value, it is not
receiving a PCI bus message for the average fuel
economy from the BCM. To check out the PCI bus
line and the BCM use the DRB llltscan tool and
proper Body Diagnostic Procedure Manual.
DISTANCE TO EMPTY
The compass mini-trip computer receives distance
to empty information from the BCM over the PCI bus
line. If compass mini-trip computer displays a dash
(-) instead of a distance to empty value, it is not
receiving a PCI bus message for the distance to
empty from the BCM. To check out the PCI bus line
8M - 6 MESSAGE SYSTEMSKJ
COMPASS/MINI-TRIP COMPUTER (Continued)

Page 600 of 1803

and the BCM use the DRB llltscan tool and proper
Body Diagnostic Procedure Manual.
INSTANTANEOUS FUEL ECONOMY
The compass mini-trip computer receives instanta-
neous fuel economy information from the BCM over
the PCI bus line. If compass mini-trip computer dis-
plays a dash (-) instead of an instantaneous fuel
economy value, it is not receiving a PCI bus message
for the instantaneous fuel economy from the BCM. To
check out the PCI bus line and the BCM use the
DRB llltscan tool and proper Body Diagnostic Pro-
cedure Manual.
TRIP ODOMETER
The compass mini-trip computer receives trip
odometer information from the Cluster over the PCI
bus line. If compass mini-trip computer displays
dashes - - instead of the trip odometer value, it is not
receiving a PCI bus message for the trip odometer
from the cluster. To check out the PCI bus line and
the Cluster, use the DRB llltscan tool and proper
Body Diagnostic Procedure Manual.
ELAPSED TIME
The compass mini-trip computer receives a PCI
bus message containing elapsed time information. If
compass mini-trip computer displays dashes --
instead of the elapsed time, it is not receiving a PCI
bus message for the elapsed time from the BCM. To
check out the PCI bus line and the BCM, use the
DRB llltscan tool and proper Body Diagnostic Pro-
cedure Manual.
COMPASS DISPLAY
To display the vehicle direction, the compass mini-
trip computer processes information from a sensor
internal to the module. The compass mini-trip com-
puter is self- calibrating and requires only variance
adjustments dependent upon location. The compass
mini-trip computer displays the label CAL whenever
the compass is in the fast calibration mode.
If all three of the following conditions listed below
occur, the vehicle must be demagnetized.
²Compass portion of the display is blank
²Temperature portion of the display is OK
²The label CAL is illuminated
If demagnetizing the vehicle is needed, refer to the
demagnetizing procedure in this section. After
demagnetizing, to calibrate the compass refer to Cal-
ibration Procedure and to set the variance refer to
Variance Procedure, both within this section. If the
compass portion of the display is still blank, replace
the compass mini-trip computer.
COMPASS MINI-TRIP COMPUTER - SELF
DIAGNOSTIC TEST
(1) With the ignition switch in the OFF position
simultaneously press the C/T and STEP buttons and
hold.
(2) Turn the ignition switch ON, then release C/T
and STEP buttons.
(3) The Compass mini-trip computer should light
all segments on the VF Display Screen for 2-4 sec-
onds. Check for segments that are not illuminated.
(4) If the compass mini-trip computer displays
PASS, the module is OK.
(5) If the compass mini-trip computer displays
FAIL, replace the module.
(6) If the compass mini-trip computer displays
bUS, check for an open or a short on the PCI bus
communication circuit.
(7) Press the C/T or the STEP button to exit the
self-diagnostic test.
REMOVAL
(1) Remove overhead console, refer to Console
Removal and Installation in this section.
(2) Remove mounting screws and release the map
lamp wire connector from the compass mini-trip com-
puter. (Fig. 6).
Fig. 6 Compass Mini-Trip Computer Retaining
Screws
1 - LAMPS
2 - MOUNTING SCREWS
KJMESSAGE SYSTEMS 8M - 7
COMPASS/MINI-TRIP COMPUTER (Continued)

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