relay MERCEDES-BENZ SPRINTER 2005 Service Repair Manual

heard during a coast, the front pinion bearing is the
source.
Differential bearings usually produce a low pitch
noise. Differential bearing noise is similar to pinion
bearing noise. The pitch of differential bearing noise
is also constant and varies only with vehicle speed.
Axle shaft bearingsproduce noise and vibration
when worn or damaged. The noise generally changes
when the bearings are loaded. Road test the vehicle.
Turn the vehicle sharply to the left and to the right.
This will load the bearings and change the noise
level. Where axle bearing damage is slight, the noise
is usually not noticeable at speeds above 30 mph.
LOW SPEED KNOCK
Low speed knock is generally caused by a worn
U-joint or by worn side-gear thrust washers. A worn
pinion shaft bore will also cause low speed knock.
VIBRATION
Vibration at the rear of the vehicle is usually
caused by a:
²Damaged drive shaft.
²Missing drive shaft balance weight(s).
²Worn or out-of-balance wheels.
²Loose wheel lug nuts.
²Worn U-joint(s).
²Loose/broken springs.
²Damaged axle shaft bearing(s).
²Loose pinion gear nut.
²Excessive pinion yoke run out.
²Bent axle shaft(s).
Check for loose or damaged front-end components
or engine/transmission mounts. These components
can contribute to what appears to be a rearend vibra-
tion. Do not overlook engine accessories, brackets
and drive belts.
NOTE: All driveline components should be exam-
ined before starting any repair.
DRIVELINE SNAP
A snap or clunk noise when the vehicle is shifted
into gear (or the clutch engaged), can be caused by:
²High engine idle speed.
²Transmission shift operation.
²Loose engine/transmission/transfer case mounts.
²Worn U-joints.
²Loose spring mounts.
²Loose pinion gear nut and yoke.
²Excessive ring gear backlash.
²Excessive side gear to case clearance.
The source of a snap or a clunk noise can be deter-
mined with the assistance of a helper. Raise the vehi-
cle on a hoist with the wheels free to rotate. Instruct
the helper to shift the transmission into gear. Listenfor the noise, a mechanics stethoscope is helpful in
isolating the source of a noise.
STANDARD PROCEDURE - DRAIN AND FILL
NOTE: Drain oil when warm.
(1) Clean area around oil fill plug and drain plug.
(2) Remove oil drain plug and drain oil (Fig. 1).
(3) Install oil drain plug and tighten to N´m 100
(74 ft. lbs.).
(4) Remove oil fill plug and fill housing up to bot-
tom edge of oil fill hole (Fig. 1).
(5) Install oil fill plug and tighten to N´m 100 (74
ft. lbs.).
REMOVAL
(1) Raise and support the vehicle.
(2) Position a suitable lifting device under the axle
and secure axle to device.
(3) Remove wheels and tires.
(4) Unplug wear indicator cable (Fig. 2) and (Fig.
3).
(5) Detach cable connector for brake pad wear
indicator.
(6) Remove ABS sensor and clamp bushing from
mounting bore.
NOTE: The right-hand ABS sensor cable is labeled
at the factory with a white tag.
(7) Remove cable ties from the park brake cables.
Release connection cable of brake pad wear indicator
and ABS sensor cable up to the relay unit of the
parking brake.
(8) Remove brake cables from adjuster.
(9) Remove brake calipers with adapters and lines.
Fig. 1 FILL PLUG
1 - FILL PLUG
2 - DRAIN PLUG
VAREAR AXLE 3 - 11
REAR AXLE (Continued)

(10) Install connection cable of brake pad wear
indicator and ABS sensor cable up to the relay unit
of the parking brake.
(11) Install cable ties to the park brake cables.
(12) Install ABS sensor and clamp bushing to
mounting bore.
NOTE: The right-hand ABS sensor cable is labeled
at the factory with a white tag.
(13) Attach connector cable for brake pad wear
indicator.
(14) Plug in cable of brake pad wear indicator.(15) Install the wheels and tires.
(16) Fill axle with appropriate lubricant.
(17) Remove lifting device from under the axle.
(18) Remove support and lower vehicle.
SPECIFICATIONS
AXLE SPECIFICATIONS
DESCRIPTION SPECIFICATION
Axle Ratio 3.73, 4.11
Ring Gear Diameter 216 mm (8.5 in.)
Fig. 3 DUAL REAR WHEEL AXLE
1 - SPRING 11 - WEAR INDICATOR CONNECTOR
2 - SPRING SHACKLE 12 - BRAKE HOSE
3 - PLATE 13 - LUG NUT
4 - COLLAR NUT 14 - NUT
5 - BRAKE CABLE 15 - WASHER
6 - REAR AXLE 16 - BOLT
7 - ALB LEVER 17 - SHOCK ABSORBER
8 - NUT 18 - PROPELLER SHAFT
9 - BOLT 19 - BOLT
10 - WEAR INDICATOR CABLE 20 - ABS SENSOR
21 - SENSOR BUSHING
VAREAR AXLE 3 - 13
REAR AXLE (Continued)

(6) Properly align the radiator assembly and
install the front end cross member.
(7) Connect negative battery cable.
ENGINE BLOCK HEATER
REMOVAL
WARNING: RISK OF INJURY TO SKIN AND EYES
DUE TO SCALDING FROM HOT COOLANT. DO NOT
OPEN THE COOLING SYSTEM UNLESS THE TEM-
PERATURE IS BELOW 194ÉF (90ÉC). WEAR PRO-
TECTIVE CLOTHING AND EYE WEAR. RISK OF
POISONING IF COOLANT IS SWALLOWED. STORE
COOLANT IN PROPER AND APPROPRIATELY
MARKED CONTAINERS.
(1) Disconnect the negative battery cable.
(2) Drain the cooling system.
(3) Record the location and snip the wire ties.
(4) Unscrew the engine block heater from the core
plug hole and remove (Fig. 6).
INSTALLATION
(1) Screw the block heater into the appropriate
core hole (Fig. 6).
(2) Route the heater wiring harness away from
and interference and secure with wiring tie straps.
(3) Refill the cooling system.
(4) Connect the negative battery cable.
(5) Start the engine and inspect for leaks.
ENGINE COOLANT TEMP
SENSOR
DESCRIPTION
The ECM determines the operating temperature of
the engine by using the signal from the coolant tem-
perature sensor. The coolant temperature sensor has
a negative temperature coefficient (NTC) resistor
contained in the plastic housing. NTC means; the
higher the temperature, then the lower the resis-
tance. The ECM also uses the coolant temperature
sensor signal to calculate glow plug relay triggering.
If the coolant temperature sensor fails during opera-
tion, the ECM will switch on the cooling fan to pre-
vent engine overheating (A/C models only).
REMOVAL
WARNING: RISK OF INJURY TO SKIN AND EYES
FROM SCALDING WITH HOT COOLANT. RISK OF
POISONING FROM SWALLOWING COOLANT. DO
NOT OPEN COOLING SYSTEM UNLESS COOLANT
TEMPERATURE IS BELOW 90ÉC. OPEN CAP
SLOWLY TO RELEASE PRESSURE. STORE COOL-
ANT IN SUITABLE AND APPROPRIATELY MARKED
CONTAINER. WEAR PROTECTIVE GLOVES,
CLOTHES AND EYE WEAR.
(1) Disconnect negative battery cable.
(2) Remove engine cover (Refer to 9 - ENGINE -
REMOVAL).
(3) Partailly drain coolant system (Refer to 7 -
COOLING/ENGINE/COOLANT - STANDARD PRO-
CEDURE).
(4) Unplug coolant temperature sensor electrical
connector.
Fig. 6 ENGINE BLOCK HEATER
1 - ENGINE BLOCK HEATER
2 - CORE PLUG
3 - ENGINE MOUNT
4 - WIRING TIE STRAPS
7 - 14 ENGINEVA
RADIATOR FAN (Continued)

CHIME/BUZZER
TABLE OF CONTENTS
page page
CHIME/BUZZER
DESCRIPTION..........................1
OPERATION............................1DIAGNOSIS AND TESTING - CHIME
WARNING SYSTEM.....................2
CHIME/BUZZER
DESCRIPTION
A chime warning system is standard factory-installed
equipment. The chime warning system uses a chime
tone generator and a contactless relay that are soldered
onto the electronic circuit board inside the ElectroMe-
chanical Instrument Cluster (EMIC) to provide audible
indications of various vehicle conditions that may
require the attention of the vehicle operator or occu-
pants. The microprocessor-based EMIC utilizes elec-
tronic messages received from other modules in the
vehicle over the Controller Area Network (CAN) data
bus network along with hard wired inputs to the cluster
to monitor many sensors and switches throughout the
vehicle. In response to those inputs, the circuitry and
internal programming of the EMIC allow it to control
audible outputs that are produced through its on-board
chime tone generator and contactless relay.
The EMIC circuitry and its chime tone generator are
capable of producing the following audible outputs:
²Single Chime Tone- A single, extended ªbeep-
likeº chime tone is issued as a seat belt reminder.
²Fast Rate Repetitive Chime Tone- Repeated
ªbeep-likeº tones that are issued at a fast rate as an
audible alert and to support various visual warnings.
²Slow Rate Repetitive Click Tone- Repeated
ªclick-likeº tones that are issued at a slow rate to
emulate turn signal and hazard flasher operation.
²Fast Rate Repetitive Click Tone-
Repeated
ªclick-likeº tones that are issued at a fast rate to emu-
late turn signal flasher operation with a bulb out.
Hard wired circuitry connects the EMIC and the var-
ious chime warning switch and sensor inputs to their
respective modules and to each other through the elec-
trical system of the vehicle. These hard wired circuits
are integral to the vehicle wire harness, which is routed
throughout the vehicle and retained by many different
methods. These circuits may be connected to each other,
to the vehicle electrical system and to the EMIC through
the use of a combination of soldered splices, splice block
connectors, and many different types of wire harness ter-
minal connectors and insulators. Refer to the appropri-
ate wiring information. The wiring information includeswiring diagrams, proper wire and connector repair pro-
cedures, 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.
The EMIC chime tone generator and contactless
relay cannot be adjusted or repaired. If the chime
tone generator or contactless relay are damaged or
faulty, the entire EMIC unit must be replaced.
OPERATION
The chime warning system components operate on
battery current received through a non-switched
fused B(+) circuit so that the system may operate
regardless of the ignition switch position. The Elec-
tro-Mechanical Instrument Cluster (EMIC) also mon-
itors the ignition switch position so that some chime
features will only occur with ignition switch in the
On position, while others occur regardless of the igni-
tion switch position.
The chime warning system provides an audible
indication to the vehicle operator or occupants under
the following conditions:
²Engine Oil Level Low Warning- Each time
the ignition switch is turned to the On position, the
EMIC chime tone generator will generate a fast rate
repetitive chime tone if electronic messages are
received over the Controller Area Network (CAN)
data bus from the Engine Control Module (ECM)
indicating that the engine level is too low. The ECM
uses internal programming and hard wired inputs
from the engine oil level and temperature sensor to
determine the engine oil level. This audible warning
occurs in concert with the visual warning provided by
the multi-function indicator in the cluster.
²Fasten Seat Belt Reminder- Each time the
ignition switch is turned to the On position, the
EMIC chime tone generator will generate a single
extended chime tone for a duration of about six sec-
onds, or until the driver side front seat belt is fas-
tened, whichever occurs first. The EMIC uses
internal programming and a hard wired input from
the driver side front seat belt switch to determine
the status of the driver side front seat belt. This
audible warning occurs independent of the visual
warning provided by the EMIC ªSeatbeltº indicator.
VACHIME/BUZZER 8B - 1

²Lights-On Warning- The EMIC chime tone
generator will generate repetitive chime tones at a
fast rate when either front door is opened with the
ignition switch in any position except On, and the
exterior lights are turned On. The EMIC uses inter-
nal programming and hard wired inputs from the left
(lighting) control stalk of the multi-function switch,
the ignition switch, and both front door jamb
switches to determine the current status of these
switches. This chime will continue to sound until the
exterior lighting is turned Off, until the ignition
switch is turned to the On position, or until both
front doors are closed, whichever occurs first.
²Key-In-Ignition Warning-
The EMIC chime
tone generator will generate repetitive chime tones at a
fast rate when the key is in the ignition lock cylinder,
the ignition switch is in any position except On, and
either front door is opened. The EMIC uses internal
programming and hard wired inputs from the key-in
ignition switch, the ignition switch, and both front door
jamb switches to determine the current status of these
switches. The chime will continue to sound until the key
is removed from the ignition lock cylinder, until the
ignition switch is turned to the On position, or until
both front doors are closed, whichever occurs first.
²Audible Turn Signal/Hazard Warning Sup-
port-
The EMIC contactless relay will generate repeti-
tive clicks at a slow rate during normal turn signal/
hazard warning operation, or at a fast rate when a turn
signal lamp bulb or circuit is inoperative, in concert with
the operation of the turn signal indicators in the cluster.
These clicks are designed to emulate the sound of the
opening and closing of the contact points in a conven-
tional electro-mechanical turn signal or hazard warning
flasher. The EMIC uses a hard wired input received from
the turn signal relay in the fuse block beneath the steer-
ing column through the turn signal or hazard warning
switch circuitry of the multi-function switch to determine
when to flash the turn signal indicators and activate the
contactless relay on the cluster electronic circuit board.
The turn signal clicks will continue to sound until the
turn signal switch is turned Off, or until the ignition
switch is turned to the Off position, whichever occurs
first. The hazard warning clicks will continue to sound
until the hazard warning switch is turned Off.
The EMIC provides chime service for all available
features in the chime warning system. The EMIC relies
upon its internal programming and hard wired inputs
from the front door ajar switches, the key-in ignition
switch, the ignition switch, the seat belt switch, and the
turn signal/hazard warning (multi-function) switches.
The EMIC relies upon electronic message inputs
received from other electronic modules over the CAN
data bus network to provide chime service for the low
engine oil level warning. Upon receiving the proper
inputs, the EMIC activates the chime tone generator orthe contactless relay to provide the audible warning to
the vehicle operator. The internal programming of the
EMIC determines the priority of each chime request
input that is received, as well as the rate and duration
of each tone that is to be generated. See the owner's
manual in the vehicle glove box for more information on
the features provided by the chime warning system.
The hard wired chime warning system inputs to
the EMIC, as well as other hard wired circuits for
this system may be diagnosed and tested using con-
ventional diagnostic tools and procedures. However,
conventional diagnostic methods may not prove con-
clusive in the diagnosis of the EMIC, the CAN data
bus network, or the electronic message inputs used
by the EMIC to provide chime warning system ser-
vice. The most reliable, efficient, and accurate means
to diagnose the EMIC, the CAN data bus network,
and the electronic message inputs for the chime
warning system requires the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
DIAGNOSIS AND TESTING - CHIME WARNING
SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, DRIVER AIRBAG, PASSENGER
AIRBAG, SEAT BELT TENSIONER, OR INSTRUMENT
PANEL COMPONENT DIAGNOSIS OR SERVICE. DIS-
CONNECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS OR SERVICE.
THIS IS THE ONLY SURE WAY TO DISABLE THE SUP-
PLEMENTAL RESTRAINT SYSTEM. FAILURE TO TAKE
THE PROPER PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
The hard wired chime warning system inputs to
the Electro-Mechanical Instrument Cluster (EMIC),
as well as other hard wired circuits for this system
may be diagnosed and tested using conventional
diagnostic tools and procedures. However, conven-
tional diagnostic methods may not prove conclusive
in the diagnosis of the EMIC, the Controller Area
Network (CAN) data bus network, or the electronic
message inputs used by the EMIC to provide chime
warning system service. The most reliable, efficient,
and accurate means to diagnose the EMIC, the CAN
data bus network, and the electronic message inputs
for the chime warning system requires the use of a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information.
8B - 2 CHIME/BUZZERVA
CHIME/BUZZER (Continued)

OPERATION
The central timer module (CTM) monitors many
hard wired switch and sensor inputs as well as those
resources it shares with other modules in the vehicle
through its communication over the programmable
communications interface (PCI) data bus network.
The internal programming and all of these inputs
allow the CTM to determine the tasks it needs to
perform and their priorities, as well as both the stan-
dard and optional features that it should provide.
The CTM then performs those tasks and provides
those features through both PCI data bus communi-
cation with other modules and hard wired outputs
through a number of driver circuits, relays, and
actuators.These outputs allow the CTM the ability to
control numerous accessory systems in the vehicle.
The CTM monitors its own internal circuitry as
well as many of its input and output circuits, and
will store a Diagnostic Trouble Code (DTC) in elec-
tronic memory for any failure it detects. These DTCs
can be retrieved and diagnosed using a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
HARD WIRED INPUTS
The hard wired inputs to the CTM include the fol-
lowing:
²Fused B(+)
²Fused ignition switch output (run-acc)
²Fused ignition switch output (run-start)
²Ground
²Key-in ignition switch sense
²Sliding door switch sense
²Passenger door switch sense
²Driver door switch sense
²PCI bus circuit
HARD WIRED OUTPUTS
The hard wired outputs of the CTM include the fol-
lowing:
²Door lock relay output
²Door unlock relay output
²VTSS indicator driver
MESSAGING
The CTM uses the following messages received
from other electronic modules over the PCI data bus:
²Airbag Deploy (ACM)
²Beep request (CMTC)
²Charging System Failure (PCM)
²Chime request (EMIC)
²Engine RPM (PCM)
²OK to Arm VTSS (PCM)
²Security indicator request (SKIM)
²System Voltage (PCM)
²Valid/Invalid Key (SKIM)
²Vehicle Distance (PCM)²Vehicle Speed (PCM)DIAGNOSIS AND TESTING - CENTRAL TIMER
MODULE
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. FAILURE
TO TAKE THE PROPER PRECAUTIONS COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
The hard wired inputs to and outputs from the
central timer module (CTM) may be diagnosed and
tested using conventional diagnostic tools and meth-
ods. Refer to the appropriate wiring information.
However, conventional diagnostic methods may not
prove conclusive in the diagnosis of the CTM. In
order to obtain conclusive testing of the CTM, the
programmable communications interface (PCI) data
bus network and all of the modules that provide
inputs to or receive outputs from the CTM must also
be checked. The most reliable, efficient, and accurate
means to diagnose the CTM, the PCI data bus net-
work, and the modules that provide inputs to, or
receive outputs from, the CTM requires the use of a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Slide the driver seat to the full forward posi-
tion.
(3) Disconnect the wire harness connector for the
seat belt latch. (Fig. 1).
(4) Remove the screws that secure the closeout
panel beneathe the driver seat cushion and remove
the panel.
(5) Remove the screws that secure the central
timer module to the bracket.
(6) Disconnect the wire harness connectors from
the central timer module.
(7) Remove the central timer module from the
vehicle.
INSTALLATION
(1) Position the central timer module in the vehicle
8E - 2 ELECTRONIC CONTROL MODULESVA
CENTRAL TIMER MODULE (Continued)

(2) Connect the wire harness connectors to the
central timer module.
(3) Install the screws that secure the central timer
module. Tighten the screws securely.
(4) Route the seat belt latch wire lead through the
hole in the closeout panel and position the panel
beneath the driver seat cushion
(5) Install the screws that secure the closeout
panel beneath the driver seat cushion. Tighten the
screws securely.
(6) Connect the wire harness connector to the seat
belt latch connector.
(7) Slide the driver seat to back to its original posi-
tion.
(8) Reconnect the negative battery cable.
CONTROLLER ANTILOCK
BRAKE
DESCRIPTION
The Controler Antilock Brake (CAB) is mounted to
the Hydraulic Control Unit (HCU) and operates the
ABS system.
REMOVAL
(1) Remove the negative battery cable from the
battery.
(2) Pull up on the CAB harness connector release
and remove connector.
(3) Remove the CAB mounting bolts.
(4) Remove the CAB from the HCU.
INSTALLATION
(1) Install CAB to the HCU.
(2) Install mounting bolts. Tighten to 2 N´m (16 in.
lbs.).
(3) Install the wiring harness connector to the
CAB and push down on the release to secure the con-
nector.
(4) Install negative battery cable to the battery.
ENGINE CONTROL MODULE
DESCRIPTION
The electronic control module (ECM) is mounted to
the left lower dash panel and consists of an electronic
printed circuit board which is designed as a multi-
layer board assembly fitted on both sides. The rout-
ing of the five wiring harness connectors at the ECM
connectors are split into interfering cables and sensi-
tive cables in order to achieve improved electromag-
netic compatibility. The ECM stores engine specific
data, monitors the connected sensor and analyzes
their measurement (Fig. 2).
Its task consists in controlling the following sys-
tems in line with the analysis of the input signals:
²Fuel Supply System
²Injected Quantity Control
²Emission Control System
²Charge Pressure Control
²Cruise Control
²A/C Compressor Shut-Off
²Pre-Heating Output Relay for the Glow Plugs
²Vehicle Theft
²Air Bag
²Monitors inputs/outputs, checks plausibility and
stores faults
²Share information with other control modules
²Diagnosis
If a sensor should fail, provided the fault is not
serious, the ECM will continue to operate the engine
in Limp-Home Mode (emergency mode) using a
default value for the missing signal. The ECM
ensures that continuing to operate the engine will
not cause damage or effect safety,otherwise a Engine
shut-off process will be carried out.Fig. 1 Central Timer Module
1 - DRIVER SEAT
2 - WIRE HARNESS CONNECTOR
3 - SCREW (2)
4 - CLOSEOUT PANEL
5 - CENTRAL TIMER MODULE
6 - WIRE HARNESS CONNECTOR (2)
7 - SCREW (2)
VAELECTRONIC CONTROL MODULES 8E - 3
CENTRAL TIMER MODULE (Continued)

REMOVAL
(1) Disconnect the negative battery cable.
(2) Disconnect the ECM harness connectors (5)
(Fig. 3).
(3) Grasp ECM and pull down firmly to release
ECM from the retaining bracket tensioning springs
(Fig. 3).
INSTALLATION
NOTE: THE ECM MUST BE PROGRAMMED TO SUP-
PORT THE VEHICLE OPTIONS PACKAGE.
(1) Position the ECM into the guide of the retain-
ing bracket (Fig. 3).
(2) Carefully push the ECM in to the bracket until
the bracket tensioning springs engage (Fig. 3).
(3) Connect the ECM wiring harness connectors
(5) (Fig. 3).
(4) Connect negative battery cable.
Fig. 2 ECM
1 - A/C PUSH BUTTON CONTROL 12 - MASS AIR FLOW SENSOR
2 - ECM 13 - CRANKSHAFT POSITION SENSOR
3 - INSTRUMENT CLUSTER 14 - OIL LEVEL, OIL TEMPERATURE AND OIL QUALITY SENSOR
4 - ABS/ASR CONTROLLER 15 - LOW FUEL PRESSURE SENSOR
5 - ANTI-THEFT CONTROLLER 16 - COOLANT TEMPERATURE SENSOR
6 - AIR BAG CONTROLLER 17 - FUEL RAIL PRESSURE SENSOR
7 - IGNITION CYLINDER TRANSCEIVER RING 18 - CAMSHAFT POSITION SENSOR
8 - GLOW PLUG RELAY 19 - CHARGE AIR PRESSURE SENSOR
9 - INTAKE AIR TEMPERATURE SENSOR 20 - FUEL TEMPERATURE SENSOR
10 - KICK DOWN SWITCH 21 - WATER IN FUEL SENSOR
11 - ACCELERATOR PEDAL SENSOR
8E - 4 ELECTRONIC CONTROL MODULESVA
ENGINE CONTROL MODULE (Continued)

TRANSMISSION CONTROL
MODULE
DESCRIPTION
The transmission control module (TCM) receives,
processes and sends various digital and analog sig-
nals related to the automatic transmission. In addi-
tion, it processes information received from other
vehicle systems, such as engine torque and speed,
accelerator pedal position, wheel speed, kick-down
switch, traction control information, etc.
The TCM is located under the driver's seat and is
connected to other control modules via a CAN bus. It
controls all shift functions to achieve smooth shift
comfort in all driving situations considering:
²Vehicle speed.
²Transmission status.
²Position of selector lever.
²Selected shift range.
²CAN signals.
²Engine Status.Engine speed limits may be reached in all gears
with full throttle or in kick-down operation. In for-
ward driving, the shift range of the forward gears
can be adjusted by the operator by tipping the selec-
tor lever to the left or right (AutoStick). However, the
TCM features a downshift inhibitor to prevent the
engine from overspeeding.
OPERATION
The transmission control module (TCM) deter-
mines the current operating conditions of the vehicle
and controls the shifting process for shift comfort and
driving situations. It receives this operating data
from sensors and broadcast messages from other
modules.
The TCM uses inputs from several sensors that are
directly hardwired to the controller and it uses sev-
eral indirect inputs that are used to control shifts.
This information is used to actuate the proper sole-
noids in the valve body to achieve the desired gear.
The shift lever assembly (SLA) has several items
that are monitored by the TCM to calculate shift
lever position. The reverse light switch, an integral
part of the SLA, controls the reverse light relay con-
trol circuit. The Brake/Transmission Shift Interlock
(BTSI) solenoid and the park lockout solenoid (also
part of the SLA) are controlled by the TCM.
The ECM and ABS broadcast messages over the
controller area network (CAN C) bus for use by the
TCM. The TCM uses this information, with other
inputs, to determine the transmission operating con-
ditions.
The TCM:
²determines the momentary operating conditions
of the vehicle.
²controls all shift processes.
²considers shift comfort and the driving situation.
The TCM controls the solenoid valves for modulat-
ing shift pressures and gear changes. Relative to the
torque being transmitted, the required pressures are
calculated from load conditions, engine rpm, vehicle
speed, and ATF temperature.
The following functions are contained in the TCM:
²Shift Program
²Downshift Safety
²Torque Converter Lock-Up Clutch.
²Adaptation.
This transmission does not have a TCM relay.
Power is supplied to the SLA and the TCM directly
from the ignition.
Fig. 3 ECM
1 - BRACKET
2 - ECM
3 - BRACKET TENSIONING SPRINGS
VAELECTRONIC CONTROL MODULES 8E - 5
ENGINE CONTROL MODULE (Continued)

STARTING SYSTEM
TABLE OF CONTENTS
page page
STARTING SYSTEM
DESCRIPTION.........................24
OPERATION...........................24
DIAGNOSIS AND TESTING - STARTING
SYSTEM............................25
SPECIFICATIONS
TORQUE - STARTER - DIESEL...........29
SPECIFICATIONS - STARTER MOTOR -
DIESEL.............................29STARTER MOTOR
DIAGNOSIS AND TESTING - STARTER
MOTOR .............................29
REMOVAL.............................30
INSTALLATION.........................31
STARTER MOTOR RELAY
DESCRIPTION.........................31
REMOVAL.............................31
INSTALLATION.........................32
STARTING SYSTEM
DESCRIPTION
The starting system consists of:
²Starter relay
²Starter motor (including an integral starter sole-
noid)
Other components to be considered as part of start-
ing system are:
²Battery
²Battery cables
²Ignition switch and key lock cylinder
²Park/neutral position switch (automatic trans-
mission)
²Wire harnesses and connections.
The Battery, Starting, and Charging systems oper-
ate in conjunction with one another, and must be
tested as a complete system. For correct operation of
starting/charging systems, all components used in
these 3 systems must perform within specifications.
When attempting to diagnose any of these systems, it
is important that you keep their interdependency in
mind.
The diagnostic procedures used in each of these
groups include the most basic conventional diagnostic
methods, to the more sophisticated On-Board Diag-
nostics (OBD) built into the Engine Control Module
(ECM). Use of an induction-type milliampere amme-
ter, volt/ohmmeter, battery charger, carbon pile rheo-
stat (load tester), and 12-volt test lamp may be
required.
Certain starting system components are monitored
by the ECM and may produce a Diagnostic Trouble
Code (DTC).
OPERATION
The starting system components form two separate
circuits. A high-amperage feed circuit that feeds thestarter motor high-amperage, and a low-amperage
control circuit that operates on less than 20 amperes.
The high-amperage feed circuit components include
the battery, the battery cables, the contact disc por-
tion of the starter solenoid, and the starter motor
itself. The low-amperage control circuit components
include the ignition switch, the park/neutral position
switch (automatic transmission), the starter relay,
the electromagnetic windings of the starter solenoid,
and the connecting wire harness components.
If the vehicle is equipped with an automatic trans-
mission, battery voltage is supplied through the low-
amperage control circuit to the coil battery terminal
of the starter relay when the ignition switch is
turned to the momentary Start position. The park/
neutral position switch is installed in series between
the starter relay coil ground terminal and ground.
This normally open switch prevents the starter relay
from being energized and the starter motor from
operating unless the automatic transmission gear
selector is in the Neutral or Park positions.
When the starter relay coil is energized, the nor-
mally open relay contacts close. The relay contacts
connect the relay common feed terminal to the relay
normally open terminal. The closed relay contacts
energize the starter solenoid coil windings.
The energized solenoid pull-in coil pulls in the sole-
noid plunger. The solenoid plunger pulls the shift
lever in the starter motor. This engages the starter
overrunning clutch and pinion gear with the starter
ring gear on the manual transmission flywheel or on
the automatic transmission torque converter or
torque converter drive plate.
As the solenoid plunger reaches the end of its
travel, the solenoid contact disc completes the high-
amperage starter feed circuit and energizes the sole-
noid plunger hold-in coil. Current now flows between
the solenoid battery terminal and the starter motor,
energizing the starter.
8F - 24 STARTING SYSTEMVA