sensor MERCEDES-BENZ SPRINTER 2006 Service Manual

volt, clean and tighten the battery negative cable
eyelet terminal connection to the engine block.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery negative cable.
REMOVAL
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Disconnect and isolate the remote battery neg-
ative cable terminal.
(3) One at a time, trace and disconnect the battery
cable retaining pushpins, fasteners and routing clips
until the cables are free from the vehicle.
(4) Feed the battery cable assembly out of the
vehicle.
INSTALLATION
(1) Position the battery cable in the vehicle.
(2) One at a time, install the battery cable retain-
ing pushpins, fasteners and routing clips until the
cable is installed exactly in the factory installed loca-
tion in the vehicle. Refer to the Wiring Diagram sec-
tion of the service manual for reference.
(3) Connect the battery negative cable terminal.
BATTERY TRAY
DESCRIPTION
The battery is mounted in a stamped steel battery
tray located in the left front corner of the engine
compartment. The battery tray is secured with bolts
to the left front wheelhouse inner steel panel. A hole
in the bottom of the battery tray is fitted with aformed drain tube. A second hole in the bottom of the
tray is fitted with a battery temperature sensor.
OPERATION
The battery tray provides a mounting location and
support for the vehicle battery. The battery tray sup-
port supports the battery tray and provides an
anchor point for the inboard battery hold down hard-
ware. The battery tray and the battery hold down
hardware combine to secure and stabilize the battery
in the engine compartment, which prevents battery
movement during vehicle operation. Unrestrained
battery movement during vehicle operation could
result in damage to the vehicle, the battery or both.
The battery tray drain tube directs spilled water or
electrolyte from a leaking battery to the ground
through another hole in the front extension of the
left front wheelhouse inner panel.
REMOVAL
(1) Remove the battery from the battery tray.
(Refer to 8 - ELECTRICAL/BATTERY SYSTEM/BAT-
TERY - REMOVAL).
(2) Remove the battery temperature sensor from
the battery tray. (Refer to 8 - ELECTRICAL/CHARG-
ING/BATTERY TEMPERATURE SENSOR -
REMOVAL).
(3) Remove the bolts that secure the battery tray
to the battery tray support.
(4) Remove the battery tray from the vehicle.
INSTALLATION
(1) Clean and inspect the battery tray. (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM - CLEANING).
(2) Position the battery tray onto the battery tray
support.
(3) Install and tighten the bolts that secure the
battery tray to the battery tray support. Tighten the
screws to 11.8 N´m (105 in. lbs.).
(4) Install the battery temperature sensor onto the
battery tray. (Refer to 8 - ELECTRICAL/CHARGING/
BATTERY TEMPERATURE SENSOR - INSTALLA-
TION).
(5) Install the battery onto the battery tray. (Refer
to 8 - ELECTRICAL/BATTERY SYSTEM/BATTERY -
INSTALLATION).
Fig. 12 Test Ground Circuit Resistance - Typical
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
8F - 16 BATTERY SYSTEMVA

HEATED SEATS
TABLE OF CONTENTS
page page
HEATED SEATS
DESCRIPTION.........................10
OPERATION...........................10
DIAGNOSIS AND TESTING - HEATED SEATS . 11
DRIVER HEATED SEAT SWITCH
DESCRIPTION.........................11
OPERATION...........................11
DIAGNOSIS AND TESTING - DRIVER HEATED
SEAT SWITCH........................11
REMOVAL.............................11
INSTALLATION.........................12
HEATED SEAT ELEMENT
DESCRIPTION.........................12
OPERATION...........................12
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENT...........................12
HEATED SEAT RELAY
DESCRIPTION.........................12OPERATION...........................13
DIAGNOSIS AND TESTING - HEATED SEAT
RELAY..............................13
REMOVAL.............................13
INSTALLATION.........................13
HEATED SEAT SENSOR
DESCRIPTION.........................13
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR............................13
PASSENGER HEATED SEAT SWITCH
DESCRIPTION.........................13
OPERATION...........................13
DIAGNOSIS AND TESTING - PASSENGER
HEATED SEAT SWITCH.................14
REMOVAL.............................14
INSTALLATION.........................14
HEATED SEATS
DESCRIPTION
Individually controlled, electrically heated front
seats are available factory-installed optional equip-
ment on this model. Vehicles with this option can be
visually identified by the two separate heated seat
switches mounted in the instrument panel. The
heated seat system allows the front seat driver and
passenger to select from two different levels of sup-
plemental electrical seat heating, or no seat heating
to suit their individual comfort requirements. The
heated seat system for this vehicle includes the fol-
lowing major components, which are described in fur-
ther detail later in this section:
²Heated Seat Elements- Four heated seat ele-
ments are used per vehicle, two for each front seat.
One heating element in the seat back and one in the
seat cushion. The heated seat sensor is integral to
the seat cushion heating element. The heated seat
elements are integral to the front seat and seat back
cushions. Refer to heated seat elements later in this
section for additional information.
²Heated Seat Relay- One heated seat relay is
used per vehicle. The relay is located in the fuse
block and is responsible for distributing the voltage
(B+) to the heated seat elements.
²Heated Seat Sensors- Two heated seat sen-
sors are used per vehicle, one for each front seat. The
heated seat sensors are integral to each of the heatedseat element assemblies. Refer to heated seat sensor
later in this section for additional information.
²Heated Seat Switches- Two heated seat
switches are used per vehicle, one for each front seat.
The switches are mounted in the instrument panel.
Refer to heated seat switches later in this section for
additional information.
Hard wired circuitry connects the heated seat sys-
tem components to each other through the electrical
system of the vehicle. Refer to Wiring for additional
information. The wiring information includes wiring
diagrams, proper wire and connector repair proce-
dures, further details on wire harness routing and
retention, as well as pin-out and location views for
the various wire harness connectors, splices and
grounds.
OPERATION
The heated seat system is designed to provide indi-
vidually controlled, supplemental heat to the seat
cushion and seat back surfaces of both front seats.
Because this system converts electrical current to
heat, the heated seat system can provide a measure
of warm comfort almost immediately upon entering a
cold vehicle, rather than having to wait for the
engine coolant to reach sufficient temperature to
deliver heat through the conventional heater system.
This system allows each front seat occupant to indi-
vidually select one of two comfort levels, Hi or Lo, or
to turn the heater for their seat off.
8G - 10 HEATED SEATSVA

The heated seat system components operate on
battery current received through a fuse in the Fuse
Block on a fused ignition switch output (run-acc) cir-
cuit so that the system will only operate when the
ignition switch is in the On or Accessory positions.
The heated seat system will be turned Off automati-
cally whenever the ignition switch is turned to any
position except On or Accessory. Also, the heated seat
system will not operate when the surface tempera-
ture of the seat cushion cover at either heated seat
sensor is above the designed temperature set points
of the system.DIAGNOSIS AND TESTING - HEATED SEATS
Refer toWiringfor the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
HEATED SEAT SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO HEATED SEAT SWITCH
ILLUMINATION WITH IGNI-
TION ON1. Faulty fuse. 1. Check heated seat fuse in Fuse Block. Re-
place fuse, if required.
2. Wiring faulty. 2. Check fused ignition switch output (run-acc)
circuit from heated seat switch connector to igni-
tion switch. Repair, if required.
3. Ground faulty. 3. Check for ground at heated seat switch con-
nector. Repair, if required.
4. Faulty switch. 4. Refer to Heated Seat Switch for the proper
switch diagnosis and testing procedures.
DRIVER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are located on the instru-
ment panel, in the accessory switch bezel. The two,
momentary rocker type switches provide a signal to
the Heated Seat Relay through separate hard wired
circuits. Each switch contains two light emitting
diodes (LED), one for each High and Low setting to
let the occupant know that the seat heater system is
on.
The heated seat switches and their LED's cannot
be repaired. If either switch is faulty or damaged the
entire switch must be replaced.
OPERATION
There are three modes that can be selected with
each of the heated seat switches: Off, Low, and High.
When the top of the switch rocker is depressed, the
low mode is selected and the low mode LED indicator
illuminates. Depressing the top of the switch rocker a
second time will turn the heated seat to Off. This
same process is repeated for High heat setting. The
heated seats will automatically return to the Off
mode anytime the vehicle ignition switch is turned
Off.Both switches provide separate hard wire inputs to
the Heated Seat Relay to indicate the selected mode.
The Heated Seat Relay responds to the heated seat
switch messages by controlling the output to the seat
heater elements of the selected seat.
DIAGNOSIS AND TESTING - DRIVER HEATED
SEAT SWITCH
For circuit description and diagrams, refer toWir-
ing.
(1) Inspect the Heated Seat Switches for apparent
damage or sticking/binding and replace if required.
Refer to Heated Seat Switch Removal and Installa-
tion in this section.
(2) Replace the heated seat switch with a known
good unit and retest the heated seat system.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the gear selector bezel trim. Refer to
the Body section for the procedure.
(3) Remove the storage bin. Refer to the Body sec-
tion for the procedure.
(4) Remove the switch bezel retaining screw and
remove the switch bezel from the instrument panel.
Refer to the Body section for the procedure.
(5) Disconnect electrical connections.
VAHEATED SEATS 8G - 11

(6) Working from the underside of the switch, gen-
tly rock the switch back and forth out of its mounting
location in the switch bezel.
INSTALLATION
(1) Install the heated seat switch in its mounting
location in the switch bezel.
(2) Connect electrical connections.
(3) Position the switch bezel and install the retain-
ing screw. Refer to the Body section for the proce-
dure.
(4) Install the storage bin. Refer to the Body sec-
tion for the procedure.
(5) Install the gear selector bezel trim. Refer to the
Body section for the procedure.
(6) Connect the negative battery cable.
HEATED SEAT ELEMENT
DESCRIPTION
The heated seat system includes two seat heating
elements in each front seat, one for the seat cushion
(Fig. 1) and the other for the seat back. All models
use two resistor wire heating elements for each seat
that are connected in series with the Heated Seat
Relay. The temperature sensor is a Negative Temper-
ature Coefficient (NTC) thermistor. One temperature
sensor is used for each seat, and it is located in the
seat cushion heating element for all models.The seat heating elements are glued onto the seat
and seat back cushions. The heated seat elements
and the temperature sensor cannot be adjusted or
repaired and, if faulty or damaged a new seat assem-
bly must be installed.
OPERATION
The heated seat elements resist the flow of electri-
cal current. When battery current is passed through
the elements, the energy lost by the resistance of the
elements is released in the form of heat. The heated
seat temperature sensor is a NTC thermistor. When
the temperature of the seat cushion cover rises, the
resistance of the sensor decreases. The heated seat
relay uses this temperature sensor input to monitor
the temperature of the seat, and regulates the cur-
rent flow to the seat heating elements accordingly.
DIAGNOSIS AND TESTING - HEATED SEAT
ELEMENT
For complete circuit diagrams, refer toWiring.
NOTE: When checking heated seat elements for
continuity, be certain to move the heating element
being checked. Moving the element, such as sitting
in the seat will eliminate the possibility of an inter-
mittent open in the element which would only be
evident if the element was in a certain position.
Failure to check the element in various positions
could result in an incomplete test.
(1) Disconnect and isolate the battery negative
cable. Disconnect the heated seat element wire har-
ness connector from under the seat cushion. Check
for continuity between the seat heater driver circuit
and ground. There should be continuity, less than 7
ohms. If OK, go to Step 2. If not OK, replace the seat
assembly.
(2) Check for continuity between the seat heater
B+ driver circuit cavity and the seat back frame.
There should benocontinuity. If OK, heating ele-
ment is OK at this time. If not OK, replace the seat
assembly.
HEATED SEAT RELAY
DESCRIPTION
The heated seat relay is an electromechanical
device that switches 12v battery current to the
heated seat elements when the relay control coil is
energized. The heated seat relay is located in the
Fuse Block, under the drivers seat. The heated seat
relay is a International Standards Organization
(ISO) relay. Relays conforming to the ISO specifica-
tions have common physical dimensions, current
capacities, terminal patterns, and terminal functions.
Fig. 1 Heated Seat Element - Typical
1 - Seat Back Wire Harness
2 - Heated Seat Wire Harness Connector
3 - Heated Seat Cushion Element
8G - 12 HEATED SEATSVA

The heated seat relay cannot be repaired or
adjusted and, if faulty or damaged, it must be
replaced.
OPERATION
The ISO relay consists of an electromagnetic coil, a
resistor or diode, and three (two fixed and one mov-
able) electrical contacts. The movable (common feed)
relay contact is held against one of the fixed contacts
(normally closed) by spring pressure. When the elec-
tromagnetic coil is energized, it draws the movable
contact away from the normally closed fixed contact,
and holds it against the other (normally open) fixed
contact. When the electromagnetic coil is de-ener-
gized, spring pressure returns the movable contact to
the normally closed position. The resistor or diode is
connected in parallel with the electromagnetic coil in
the relay, and helps to dissipate voltage spikes that
are produced when the coil is de-energized.
DIAGNOSIS AND TESTING - HEATED SEAT
RELAY
The heated seat relay is located in the Fuse Block,
under the drivers seat. Refer toWiringfor the loca-
tion of complete heated seat system wiring diagrams.
(1) Remove the heated seat relay from the fuse
block.
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   5 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, check the relay supply circuits. If not
OK, replace the faulty relay.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) The heated seat relay is located in the fuse
block, under the drivers seat. Refer to wiring for
detailed location.
(3) Grasp the heated seat relay firmly and pull it
straight out from the fuse block. A slight rocking
motion will aid in removal.
INSTALLATION
(1) Grasp the heated seat relay firmly and push it
straight in the fuse block.
(2) Reconnect the battery negative cable.
HEATED SEAT SENSOR
DESCRIPTION
The heated seat temperature sensor is a Negative
Temperature Coefficient (NTC) thermistor. One tem-
perature sensor is used for each seat. The sensor is
located in the seat cushion heating element for all
models.
The heated seat sensor cannot be adjusted or
repaired and if it is found to be faulty, the complete
heated seat element must be replaced.
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR
For complete circuit diagrams, refer toWiring.
NOTE: Any resistance values (ohmsV) given in the
following text are supplied using the automatic
range generated by a FLUKETautomotive meter. If
another type of measuring device is used the val-
ues generated may not be the same as the results
shown here, or may have to be converted to the
range used here.
(1) Backprobe the heated seat relay wire harness
connector, do not disconnect. Using an voltmeter,
check the voltage of the seat temperature sensor
input cavity of the heated seat relay wire harness
connector. The seat sensor input voltage should be
between 1.7 volts and 3.0 volts with the system ON.
If OK, sensor is OK at this time. If not OK, replace
the faulty seat cushion heating element and sensor
assembly.
PASSENGER HEATED SEAT
SWITCH
DESCRIPTION
The heated seat switches are located on the instru-
ment panel, in the accessory switch bezel. The two,
momentary rocker type switches provide a signal to
the Heated Seat Relay through separate hard wired
circuits. Each switch contains two light emitting
diodes (LED), one for each High and Low setting to
let the occupant know that the seat heater system is
on.
The heated seat switches and their LED's cannot
be repaired. If either switch is faulty or damaged the
entire switch must be replaced.
OPERATION
There are three modes that can be selected with
each of the heated seat switches: Off, Low, and High.
When the top of the switch rocker is depressed, the
low mode is selected and the low mode LED indicator
illuminates. Depressing the top of the switch rocker a
VAHEATED SEATS 8G - 13

IGNITION CONTROL
TABLE OF CONTENTS
page page
IGNITION CONTROL
OPERATION - GLOW PLUG................1
SPECIAL TOOLS........................1
GLOW PLUG
REMOVAL.............................1
INSTALLATION..........................1GLOW PLUG RELAY
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING - GLOW PLUG
RELAYS..............................2
IGNITION CONTROL
OPERATION - GLOW PLUG
Pre - Glowing
With the key in the On position, the glow plug out-
put stage and the indicator lamp are actuated by the
ECM. The pre-heating time is calculated by the ECM
in line with the coolant temperature. The glow plug
output stage switches the current through the glow
plugs. The glow plug indicator lamp goes out after a
pre-glow period has elapsed. Component or cable fail-
ures in the pre-glow system are indicated by the glow
plug lamp and stored in the ECM.
Glow Output Stage
With the ignition key in the On position a signal is
transmitted from the ECM to the glow plug output
stager. If no data is exchanged with the ECM the
glow plug stage is terminated after two seconds. The
glow plug out put stage constantly signals the cur-
rent operating state (ON/OFF) and any system
faults. The following faults are recognized by the out
put stage and transmitted to the ECM:
²Open circuit in one or more of the glow plug
leads
²Short circuit in the glow plug circuit
²Out put stage fault or temperature related shut-
off
If a failure in the glow plug system occurs, the
glow plug indicator lamp will be illuminated only as
long as the fault is current. If the failure is no longer
present, the glow plug indicator lamp will be
switched off but a code will be stored in the ECM.
After Glow
Once the engine has started, the ECM determines
the after glow time depending on cooling tempera-
ture. During this time the glow plugs continue to be
actuated by the glow plug output stage. This results
in improved smooth running after a cold start and
improved warming up properties, elimination of blueexhaust after a cold start up and a more stable cold
starting speed.
If no signal is received from the coolant tempera-
ture sensor the signal from the oil sensor is used as a
substitute.
SPECIAL TOOLS
GLOW PLUG
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove the engine cover.
(3) Use special tool #9286 pliers to unplug the
glow plug wiring harness connector(s) at the glow
plug.
(4) Remove the glow plug(s) (Fig. 1).
INSTALLATION
(1) Screw glow plug(s) into cylinder head and
tighten to 12 N´m (115 lbs. in) (Fig. 1).
(2) Connect the glow plug wiring harness connec-
tor(s)
(3) Install the engine cover.
(4) Connect negative battery cable.
GLOW PLUG RELAY
DESCRIPTION
The glow plug relay supplies battery voltage to the
glow plug through a timed cycle that is related to
coolant temperature. The glow plug relay is located
under the battery. The purpose of a glow plug system
GLOW PLUG PLIERS
VAIGNITION CONTROL 8I - 1

is to improve combustion for low emissions and to
achieve easy starting at low temperatures.
OPERATION
When the ignition key is turned to the ON posi-
tion, the glow plug output stage and pre-glow indica-
tor lamp are actuated by the ECM. The duration of
the signal depends on the coolant temperature. The
glow plug relay has processing that communicates
with the ECM. If no data exchange occurs at the trig-
gering stage, the preheating is switched off after 2
seconds.
Start glowing is initiated when the key is in the
start position. The glow plugs (R13±R17) continue to
be supplied with voltage. This makes it possible to
stabilize the cold starting speed. (After glowing is ini-
tiated when the starter reject speed is reached).
After the engine starts, the ECM determines the
afterglow period in line with coolant temperature. If
no signal is received from the coolant temperature
sensor, afterglow is maintained for thirty seconds.
The following aims are reached by the afterglow :
²Improvement in warming-up properties
²Prevention of white exhaust smoke after cold
start
²Stabilizing of the cold starting speed
The glow plug output stage constantly signals the
current operating state and faults. The following are
faults detected and transmitted to the ECM :²Open circuit at one or several glow plugs
²Short circuit in the glow plug circuit
²Relay fault
If the Glow plug relay detects an open circuit at a
glow plug, it is stored and indicated only once the
engine is running by the preglow indicator lamp com-
ing on for about one minute and a fault is stored in
the ECM. If a short circuit, a glow plug output stage
faulty or a temperature related switching off of out-
put stages is detected, the fault is stored and indi-
cated immediately by the preglow indicator lamp
coming on. Once the fault is no longer current, the
indicator is immediately switched off, but the fault is
stored in the ECM. If the fault is constantly current,
the preglow indicator lamp remains on until the igni-
tion is switched off.
DIAGNOSIS AND TESTING - GLOW PLUG
RELAYS
Refer to the appropriate Diesel Powertrain Diagno-
sis Manual for information on diagnosing the glow
plug relays.
Fig. 1 GLOW PLUG (S)
1 - GLOW PLUG
2 - WIRING HARNESS CONNECTOR3 - INTAKE MANIFOLD
4 - ENGINE COVER
8I - 2 IGNITION CONTROLVA

Located between the rear cover and the cluster
hood is the cluster housing. The molded plastic clus-
ter housing serves as the carrier for the cluster elec-
tronic circuit board and circuitry, the cluster
connector receptacles, the gauges, a Light Emitting
Diode (LED) for each cluster indicator and general
illumination lamp, the multi-function indicator LCD
unit, electronic tone generators, the cluster overlay,
the gauge pointers, the multi-function indicator
switches and the four switch push buttons.
The cluster overlay is a laminated plastic unit. The
dark, visible, outer surface of the overlay is marked
with all of the gauge dial faces and graduations, but
this layer is also translucent. The darkness of this
outer layer prevents the cluster from appearing clut-
tered or busy by concealing the cluster indicators
that are not illuminated, while the translucence of
this layer allows those indicators and icons that are
illuminated to be readily visible. The underlying
layer of the overlay is opaque and allows light from
the LED for each of the various indicators and illu-
mination lamps behind it to be visible through the
outer layer of the overlay only through predeter-
mined cutouts. A rectangular opening in the overlay
at the base of the speedometer provides a window
through which the illuminated multi-function indica-
tor LCD unit can be viewed.
Several versions of the EMIC module are offered
on this model. These versions accommodate all of the
variations of optional equipment and regulatory
requirements for the various markets in which the
vehicle will be offered. The microprocessor-based
EMIC utilizes integrated circuitry, Electrically Eras-
able Programmable Read Only Memory (EEPROM)
type memory storage, information carried on the
Controller Area Network (CAN) data bus, along with
several hard wired analog and multiplexed inputs to
monitor systems, sensors and switches throughout
the vehicle.
In response to those inputs, the hardware and soft-
ware of the EMIC allow it to control and integrate
many electronic functions and features of the vehicle
through both hard wired outputs and the transmis-
sion of electronic message outputs to other electronic
modules in the vehicle over the CAN data bus. (Refer
to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/COMMUNICATION - DESCRIPTION -
CAN BUS).
Besides typical instrument cluster gauge and indi-
cator support, the electronic functions and features
that the EMIC supports or controls include the fol-
lowing:
²Active Service System- In vehicles equipped
with the Active Service SYSTem (ASSYST) engine oil
maintenance indicator option, the EMIC electronic
circuit board includes a second dedicated micropro-
cessor. This second microprocessor evaluates various
data including time, mileage, and driving conditionsto calculate the required engine oil service intervals,
and provides both visual and audible alerts to the
vehicle operator when certain engine oil maintenance
services are required.
²Audible Warnings- The EMIC electronic cir-
cuit board is equipped with an audible tone generator
and programming that allows it to provide various
audible alerts to the vehicle operator, including buzz-
ing and chime tones. An audible contactless elec-
tronic relay is also soldered onto the circuit board to
produce audible clicks that is synchronized with turn
signal indicator flashing to emulate the sounds of a
conventional turn signal or hazard warning flasher.
These audible clicks can occur at one of two rates to
emulate both normal and bulb-out turn or hazard
flasher operation. (Refer to 8 - ELECTRICAL/
CHIME/BUZZER - DESCRIPTION).
²Panel Lamps Dimming Control- The EMIC
provides a hard wired 12-volt Pulse-Width Modulated
(PWM) output that synchronizes the dimming level
of all panel lamps dimmer controlled lamps with that
of the cluster general illumination lamps and multi-
function indicator.
The EMIC houses four analog gauges and has pro-
visions for up to nineteen indicators (Fig. 3). The
EMIC includes the following analog gauges:
²Coolant Temperature Gauge
²Fuel Gauge
²Speedometer
²Tachometer
The EMIC includes provisions for the following
indicators (Fig. 3):
²Airbag (SRS) Indicator
²Antilock Brake System (ABS) Indicator
²Brake Indicator
²Brake Wear Indicator
²Charging Indicator
²Clogged Fuel Filter Indicator
²Constant Engine Speed (ADR) Indicator
²Coolant Low Indicator
²Electronic Stability Program (ESP) Indica-
tor
²High Beam Indicator
²Low Fuel Indicator
²Malfunction Indicator Lamp (MIL)
²Multi-Function Indicator (LCD)
²Park Brake Indicator
²Seatbelt Indicator
²Traction Control (ASR) Indicator
²Traction Control (ASR) Malfunction Indica-
tor
²Turn Signal (Right and Left) Indicators
²Washer Fluid Indicator
²Wait-To-Start Indicator
²Water-In-Fuel Indicator
VAINSTRUMENT CLUSTER 8J - 3

INDICATORS
Indicators are located in various positions within
the EMIC and are all connected to the EMIC elec-
tronic circuit board. The ambient temperature indica-
tor (optional), brake indicator, brake wear indicator,
charging indicator, coolant low indicator, high beam
indicator, low fuel indicator, park brake indicator,
seatbelt indicator, turn signal indicators, and washer
fluid indicator operate based upon hard wired inputs
to the EMIC. The airbag (SRS) indicator is normally
controlled by a hard wired input from the Airbag
Control Module (ACM); however, if the EMIC sees an
abnormal or no input from the ACM, it will automat-
ically turn the airbag indicator On until the hard
wired input from the ACM has been restored. The
Malfunction Indicator Lamp (MIL) is normally con-
trolled by CAN data bus messages from the Engine
Control Module (ECM); however, if the EMIC loses
CAN data bus communication, the EMIC circuitry
will automatically turn the MIL on until CAN data
bus communication is restored. The EMIC uses CAN
data bus messages from the ECM, the ACM, and the
Controller Antilock Brake to control all of the
remaining indicators.
The various EMIC indicators are controlled by dif-
ferent strategies; some receive battery feed from the
EMIC circuitry and have a switched ground, while
others are grounded through the EMIC circuitry and
have a switched battery feed. However, all indicators
are completely controlled by the EMIC microproces-
sor based upon various hard wired and electronic
message inputs. Except for the indications provided
by the multi-function indicator Liquid Crystal Dis-
play (LCD) unit, all indicators are illuminated at a
fixed intensity, which is not affected by the selected
illumination intensity of the EMIC general illumina-
tion lamps.
The hard wired indicator inputs may be diagnosed
using conventional diagnostic methods. However,
proper testing of the EMIC circuitry and the CAN
bus message controlled indicators requires the use of
a diagnostic scan tool. Refer to the appropriate diag-
nostic information. Specific details of the operation
for each indicator may be found elsewhere in this
service information.
CLUSTER ILLUMINATION
The EMIC has several general illumination lamps
that are illuminated when the exterior lighting is
turned on with the multi-function switch. The illumi-
nation intensity of these lamps is adjusted by a dim-
ming level input received from the multi-function
indicator ª+º (plus) and ª±º (minus) switch push but-
tons that extend through the lower edge of the clus-
ter lens below the right end of the multi-function
indicator. When the exterior lighting is turned Off,
the display is illuminated at maximum brightness.
When the exterior lighting is turned On and thetransmission gear selector is in the Park position,
depressing the plus switch push button brightens the
display lighting, and depressing the minus switch
push button dims the display lighting. The EMIC
also provides a Pulse-Width Modulated (PWM) panel
lamps dimmer output that can be used to synchro-
nize the illumination lighting levels of external illu-
mination lamps (up to about 23 to 30 watts) with
that of the EMIC.
The hard wired multi-function switch input and
the EMIC panel lamps dimmer output may be diag-
nosed using conventional diagnostic methods. How-
ever, proper testing of the PWM control of the EMIC
and the electronic dimming level inputs from the
multi-function indicator push buttons requires the
use of a diagnostic scan tool. Refer to the appropriate
diagnostic information.
INPUT AND OUTPUT CIRCUITS
HARD WIRED INPUTS
The hard wired inputs to the EMIC include the fol-
lowing:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
²Airbag Indicator Driver
²Ambient Temperature Sensor Signal
(Optional)
²Brake Wear Indicator Sense
²Charging Indicator Driver
²Coolant Level Switch Sense
²Front Door Jamb Switch Sense
²Fuel Level Sensor Signal
²Fused B(+)
²Fused Ignition Switch Output
²High Beam Indicator Driver
²Key-In Ignition Switch Sense
²Left Turn Signal
²Park Brake Switch Sense
²Right Turn Signal
²Seat Belt Switch Sense
²Washer Fluid Switch Sense (Optional)
Refer to the appropriate wiring information for
additional details.
HARD WIRED OUTPUTS
The hard wired outputs of the EMIC include the
following:
²Engine Running Relay Control
²Panel Lamps Driver
Refer to the appropriate wiring information for
additional details.
8J - 6 INSTRUMENT CLUSTERVA

GROUNDS
The EMIC receives and supplies a ground path to
several switches and sensors through the following
hard wired circuits:
²Ambient Temperature Sensor Return
(Optional)
²Fuel Level Sensor Return
²Ground
Refer to the appropriate wiring information for
additional details.
COMMUNICATION
The EMIC has provisions for the following commu-
nication circuits:
²CAN Data Bus - High
²CAN Data Bus - Low
²Diagnostic Serial Communication Interface
(SCI) Data Bus Line
Refer to the appropriate wiring information for
additional details.
DIAGNOSIS AND TESTING - INSTRUMENT
CLUSTER
The hard wired inputs to and outputs from the
instrument cluster may be diagnosed and tested
using conventional diagnostic tools and procedures.
Refer to the appropriate wiring information. The wir-
ing information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
If the instrument cluster is completely inoperative,
be certain to check the fused B(+) circuit fuses and
wiring for the instrument cluster. If the cluster gen-
eral illumination is inoperative, be certain to check
the instrument lighting fuse and the input circuit to
the instrument cluster from the exterior lighting cir-
cuitry of the multi-function switch on the steering
column.
Conventional diagnostic methods may not prove
conclusive in the diagnosis of the instrument cluster.
In order to obtain conclusive testing of the instru-
ment cluster, the Controller Area Network (CAN)
data bus network and all of the electronic modules
that provide inputs to or receive outputs from the
instrument cluster must also be checked. The most
reliable, efficient, and accurate means to diagnose
the instrument cluster, the CAN data bus network,
and the electronic modules that provide inputs to or
receive outputs from the instrument cluster requires
the use of a diagnostic scan tool and the appropriate
diagnostic information. The diagnostic scan tool can
provide confirmation that the CAN data bus network
is functional, that all of the modules are sending and
receiving the proper electronic messages over the
CAN data bus, and that the instrument cluster isreceiving the proper hard wired inputs and respond-
ing with the proper hard wired outputs needed to
perform its many functions.
WARNING: To avoid personal injury or death, on
vehicles equipped with airbags, disable the supple-
mental restraint system before attempting any
steering wheel, steering column, airbag, seat belt
tensioner, or instrument panel component diagno-
sis or service. Disconnect and isolate the battery
negative (ground) cable, then wait two minutes for
the system capacitor to discharge before perform-
ing further diagnosis or service. This is the only
sure way to disable the supplemental restraint sys-
tem. Failure to take the proper precautions could
result in accidental airbag deployment.
STANDARD PROCEDURE
CLUSTER PROGRAMMING
NOTE: After replacing the Instrument Cluster (IC)
according to the service procedures, determine the
optional equipment on the vehicle by accessing the
sales code information using the Vehicle Identifica-
tion Number (VIN) on DealerCONNECT.
(1) Using the DRBIIIt, selectMISCELLANEOUS
FUNCTIONSin the Instrument Cluster (IC) section.
(2) SelectMODULE SERVICE REPLACE-
MENT.
(3) Following the prompts on the DRBIIIt, enter
the correct parameters that are applicable to the
vehicle. Use the sales code information and visual
inspection to obtain the correct parameters.
CAUTION: Do not lock down the instrument cluster
until the following steps are followed or the instru-
ment cluster may be irreversibly damaged.
(4) After entering the proper parameters into the
IC, turn the ignition switch to the OFF position for
30 seconds, then turn the ignition switch ON.
(5) Test drive the vehicle for at least 10 minutes
before proceeding.
(6) Check ALL modules for any parameterization
DTCs. If any parameterization DTCs are present, one
or more parameters entered into the IC are incorrect.
Verify all parameters entered using the sales code
information and visual inspection of the vehicle.
(7) If the parameters entered are verified as cor-
rect and parameterization DTCs are still present,
refer to the appropriate diagnostic information.
(8) If no parameterization DTCs are present, lock
down the IC.
VAINSTRUMENT CLUSTER 8J - 7