sensor MERCEDES-BENZ SPRINTER 2005 Service Owner's Manual

INSTALLATION
(1) Clean all sealing surfaces.
(2) Position and install thermostat housing with
new gasket (Fig. 8). Tighten bolts to 9N´m (80
lbs.in.).
NOTE: Inspect condition of all clamps and hoses,
replace as necessary.
(3) Install cap at oil filter housing.
(4) Connect coolant hoses and vent hose (Fig. 8).
(5) Install bracket for fuel line (Fig. 8).
(6) Attach air intake hose at charge air distribu-
tion pipe.
(7) Close coolant drain.
(8) Connect negative battery cable.
(9) Fill coolant system to proper level with appro-
priate coolant mixture (Refer to 7 - COOLING/EN-
GINE/COOLANT - STANDARD PROCEDURE).
WARNING: USE EXTREME CAUTION WHEN ENGINE
IS OPERATING. DO NOT STAND IN DIRECT LINE
WITH FAN. DO NOT PUT YOUR HANDS NEAR PUL-
LEYS, BELTS OR FAN. DO NOT WEAR LOOSE
CLOTHES.
(10) Start engine and inspect for leaks.
FAN DRIVE VISCOUS CLUTCH
REMOVAL
(1) For fan drive viscous clutch removal refer to
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
REMOVAL).
INSTALLATION
(1) For fan drive viscous clutch installation refer to
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
RADIATOR
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 (194ÉF). OPEN CAP
SLOWLY TO RELEASE PRESSURE. STORE COOL-
ANT IN SUITABLE AND APPROPRIATELY MARKED
CONTAINER. WEAR PROTECTIVE GLOVES,
CLOTHES AND EYE WEAR.
NOTE: Capture all residual fluid spillage and store
in suitably marked containers. Inspect condition of
all clamps and hoses, replace as necessary.
(1) Drain coolant from radiator only(Refer to 7 -
COOLING/ENGINE/COOLANT - STANDARD PRO-
CEDURE).
(2) Remove headlamp.
(3) Remove front cross member together with front
grille.
(4) Remove front bumper.
(5) Evacuate air conditioning.
(6) Remove A/C condenser.
(7) Detach charge air hose at turbocharger (Fig. 9).
(8) Detach charge air hose at air intake pipe (Fig.
9).
(9) Detach air intake pipe at the body (Fig. 9).
(10) Detach coolant hoses at the coolant reservoir
(Fig. 9).
(11) Unplug wiring connector at coolant level sen-
sor (Fig. 9).
(12) Drain steering gear oil from reservoir of
power steering pump.
(13) Detach the hydraulic oil hose at reservoir of
power steering pump.
(14) Detach the hydraulic oil hose at hydraulic oil
line.
Fig. 8 THERMOSTAT HOUSING ASSEMBLY
1 - O-RING
2 - CLAMP
3 - COOLANT TEMPERATURE SENSOR
4 - FUEL LINE W/BRACKET
5 - THERMOSTAT HOUSING ASSEMBLY
6 - COOLANT HOSE
7 - CLAMP
8 - COOLANT HOSE
9 - GASKET
7 - 16 ENGINEVA
ENGINE COOLANT THERMOSTAT (Continued)

(15) Detach coolant hose at bottom right of radia-
tor (Fig. 9).
(16) Detach transmission cooler lines (Fig. 9).
(17) Remove the radiator trim from the left and
right (Fig. 9).
(18) Lift the radiator assembly up and out of the
rubber grommets (Fig. 9).
(19) Remove top radiator trim.
(20) Take off charge air cooler together with cool-
ing loop of the steering at the radiator (Fig. 10).
(21) Remove bottom radiator trim (Fig. 10).
(22) Detach coolant hose at radiator.
(23) Detach coolant pipe together with coolant
hose at the fan shroud.
(24) Remove radiator fan shroud (Fig. 10).
INSTALLATION
(1) Install fan shroud to radiator (Fig. 10).
(2) Attach coolant pipe with hoses to fan shroud
(Fig. 10).(3) Attach coolant hose at radiator (Fig. 10).
(4) Install bottom radiator trim (Fig. 10).
(5) Install charge air cooler along with cooling loop
of the power steering, to radiator (Fig. 10).
(6) Install radiator assembly into the rubber grom-
mets (Fig. 9).
(7) Install both right and left side radiator trim
panels (Fig. 9).
(8) Attach the transmission cooler lines (Fig. 9).
(9) Attach coolant hose to the bottom right of the
radiator (Fig. 9).
(10) Attach both power steering hydraulic lines
(Fig. 9).
(11) Connect coolant level sensor electrical connec-
tor (Fig. 9).
(12) Connect coolant hoses to the coolant reservoir,
radiator and water pump (Fig. 9).
(13) Attach air intake pipe at the body.
(14) Attach charge air hose at air intake.
(15) Attach charge air hose at turbocharger.
Fig. 9 RADIATOR ASSEMBLY
1 - COOLANT HOSE 8 - ATF LINE
2 - SENSOR HARNESS CONNECTOR 9 - LEFT RADIATOR TRIM PANEL
3 - HYDRAULIC HOSE 10 - RIGHT RADIATOR TRIM PANEL
4 - CHARGE AIR HOSE 11 - RADIATOR
5 - HYDRAULIC HOSE 12 - ATF LINE
6 - RUBBER GROMMET 13 - COOLANT HOSE
7 - COOLANT HOSE 14 - COOLANT RESERVOIR
VAENGINE 7 - 17
RADIATOR (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

ELECTRONIC CONTROL MODULES
TABLE OF CONTENTS
page page
CENTRAL TIMER MODULE
DESCRIPTION..........................1
OPERATION............................2
DIAGNOSIS AND TESTING - CENTRAL TIMER
MODULE.............................2
REMOVAL.............................2
INSTALLATION..........................2
CONTROLLER ANTILOCK BRAKE
DESCRIPTION..........................3
REMOVAL.............................3INSTALLATION..........................3
ENGINE CONTROL MODULE
DESCRIPTION..........................3
REMOVAL.............................4
INSTALLATION..........................4
TRANSMISSION CONTROL MODULE
DESCRIPTION..........................5
OPERATION............................5
STANDARD PROCEDURE - TCM ADAPTATION . 8
CENTRAL TIMER MODULE
DESCRIPTION
The central timer module (CTM) is located beneath
the driver seat. The CTM uses information carried on
the programmable communications interface (PCI)
data bus network along with many hard wired inputs
to monitor many sensor and switch inputs. In
response to those inputs, the circuitry and program-
ming of the CTM allow it to supply the vehicle occu-
pants with audible and visual information, and to
control and integrate many functions and features of
the vehicle through both hard wired outputs and the
transmission of message outputs to other modules in
the vehicle over the PCI data bus.
The features that the CTM supports or controls
include the following:
²Central Locking- The CTM on vehicles
equipped with the optional Vehicle Theft Security
System (VTSS) includes a central locking/unlocking
feature.
²Enhanced Accident Response- The CTM pro-
vides an optional enhanced accident response fea-
ture. This is a programmable feature.
²Panic Mode- The CTM provides support for
the optional RKE system panic mode including horn,
headlamp, and park lamp flash features.
²Power Lock Control- The CTM provides the
optional power lock system features, including sup-
port for the automatic door lock and door lock inhibit
modes.²Programmable Features- The CTM provides
support for certain programmable features.
²Remote Keyless Entry- The CTM provides
the optional Remote Keyless Entry (RKE) system fea-
tures, including support for the RKE Lock (with
optional horn and park lamps flash), Unlock (with
park lamps flash, driver-door-only unlock, and
unlock-all-doors), Panic, and illuminated entry
modes, as well as the ability to be programmed to
recognize up to four RKE transmitters. The RKE
horn, driver-door-only unlock, and unlock-all-doors
features are programmable.
²Vehicle Theft Security System- The CTM
provides control of the optional Vehicle Theft Secu-
rity System (VTSS) features, including support for
the central locking/unlocking mode and control of the
Security indicator in the instrument cluster.
Hard wired circuitry connects the CTM to the elec-
trical system of the vehicle. Refer to the appropriate
wiring information.
Many of the features in the vehicle controlled or
supported by the CTM are programmable using the
DRBIIItscan tool. However, if any of the CTM hard-
ware components are damaged or faulty, the entire
CTM unit must be replaced. The hard wired inputs
or outputs of all CTM versions can be diagnosed
using conventional diagnostic tools and methods;
however, for diagnosis of the CTM or the PCI data
bus, the use of a DRBIIItscan tool is required. Refer
to the appropriate diagnostic information.
VAELECTRONIC CONTROL MODULES 8E - 1

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)

The TCM continuously checks for electrical prob-
lems, mechanical problems, and some hydraulic prob-
lems. When a problem is sensed, the TCM stores a
diagnostic trouble code (DTC). Some of these codes
cause the transmission to go into9Limp-In9or
9default9mode. Some DTCs cause permanent
Limp-In and others cause temporary Limp-In. The
NAG1 defaults in the current gear position if a DTC
is detected, then after a key cycle the transmission
will go into Limp-in, which is mechanical 2nd gear.
Some DTCs may allow the transmission to resume
normal operation (recover) if the detected problem
goes away. A permanent Limp-In DTC will recover
when the key is cycled, but if the same DTC is
detected for three key cycles the system will not
recover and the DTC must be cleared from the TCM
with the DRBIIItscan tool.
TCM SIGNALS
The TCM registers one part of the input signals by
direct inputs, the other part by CAN C bus. In addi-
tion to the direct control of the actuators, the TCM
sends various output signals by CAN C bus to other
control modules.
Selector Lever Position
The TCM monitors the SLA for all shift lever posi-
tions via the CAN bus.
ATF Temperature Sensor
The ATF temperature sensor is a positive temper-
ature co-efficient (PTC) thermistor. It measures the
temperature of the transmission fluid and is a direct
input signal for the TCM. The temperature of the
ATF has an influence on the shifttime and resulting
shift quality. As the temperature rises, resistance
rises, and therefore, the probing voltage is decreas-
ing. Because of its registration, the shifting process
can be optimized in all temperature ranges.
The ATF temperature sensor is wired in series
with the park/neutral contact. The temperature sig-
nal is transmitted to the TCM only when the reed
contact of the park/neutral contact is closed because
the TCM only reads ATF temperature while in any
forward gear, or REVERSE. When the transmission
is in PARK or NEUTRAL, the TCM will substitute
the engine temperature for the ATF temperature.
Starter Interlock
The TCM monitors a contact switch wired in series
with the transmission temperature sensor to deter-
mine PARK and NEUTRAL positions. The contact
switch is open in PARK and NEUTRAL. The TCM
senses transmission temperature as high (switch
supply voltage), confirming switch status as open.
The TCM then broadcasts a message over CAN bus
to confirm switch status. The PCM receives thisinformation and allows operation of the starter cir-
cuit.
N2 and N3 Speed Sensors
The N2 and N3 Input Speed Sensors are two Hall-
effect speed sensors that are mounted internally in
the transmission and are used by the TCM to calcu-
late the transmission's input speed. Since the input
speed cannot be measured directly, two of the drive
elements are measured. Two input speed sensors
were required because both drive elements are not
active in all gears.
CAN C Bus Indirect Input Signals
A 2.5-volt bias (operating voltage) is present on the
CAN C bus any time the ignition switch is in the
RUN position. Both the TCM and the ABS apply this
bias. On this vehicle, the CAN C bus is used for mod-
ule data exchange only. The indirect inputs used on
the NAG1 electronic control system are:
²Wheel Speed Sensors.
²Brake Switch.
²Engine RPM.
²Engine Temperature.
²Cruise Control Status.
²Gear Limit Request.
²Throttle Position - 0% at idle, 100% at WOT. If
open, TCM assumes idle (0% throttle opening).
²Odometer Mileage
²Maximum Effective Torque.
²Engine in Limp-In Mode/Mileage Where DTC
Was Set.
BRAKE TRANSMISSION SHIFT INTERLOCK (BTSI)
The BTSI solenoid prevents shifting out of the
PARK position until the ignition key is in the RUN
position and the brake pedal is pressed. The TCM
controls the ground while the ignition switch supplies
power to the BTSI solenoid. The PCM monitors the
brake switch and broadcasts brake switch status
messages over the CAN C bus. If the park brake is
depressed and there is power (Run/Start) to SLA, the
BTSI solenoid deactivates.
SHIFT SCHEDULES
The basic shift schedule includes up and down-
shifts for all five gears. The TCM adapts the shift
program according to driving style, accelerator pedal
position and deviation of vehicle speed. Influencing
factors are:
²Road Conditions.
²Incline, Decline and Altitude.
²Trailer Operation, Loading.
²Engine Coolant Temperature.
²Cruise Control Operation.
²Sporty Driving Style.
8E - 6 ELECTRONIC CONTROL MODULESVA
TRANSMISSION CONTROL MODULE (Continued)

(clutch or brake). Fill time adaptation is the ability of
the TCM to modify the time it takes to fill the shift
member by applying a preload pressure.
CONTROLLER MODES OF OPERATION
Permanent Limp-In Mode
When the TCM determines there is a non-recover-
able condition present that does not allow proper
transmission operation, it places the transmission in
permanent Limp-In Mode. When the condition occurs
the TCM turns off all solenoids as well as the sole-
noid supply output circuit. If this occurs while the
vehicle is moving, the transmission remains in the
current gear position until the ignition is turned off
or the shifter is placed in the9P9position. When the
shifter has been placed in9P,9the transmission only
allows 2nd gear operation. If this occurs while the
vehicle is not moving, the transmission only allows
operation in 2nd gear.
Temporary Limp-In Mode
This mode is the same as the permanent Limp-In
Mode except if the condition is no longer present, the
system resumes normal operation.
Under Voltage Limp-In Mode
When the TCM detects that system voltage has
dropped below 8.5 volts, it disables voltage-depen-
dant diagnostics and places the transmission in the
temporary Limp-In Mode. When the TCM senses
that the voltage has risen above 9.0 volts, normal
transmission operation is resumed.
Hardware Error Mode
When the TCM detects a major internal error, the
transmission is placed in the permanent Limp-In
Mode and ceases all communication over the CAN
bus. When the TCM has entered this mode normal
transmission operation does not resume until all
DTCs are cleared from the TCM.
Loss of Drive
If the TCM detects a situation that has resulted or
may result in a catastrophic engine or transmission
problem, the transmission is placed in the neutral
position. Improper Ratio, Input Sensor Overspeed or
Engine Overspeed DTCs cause the loss of drive.
Controlled Limp-in Mode
When a failure does not require the TCM to shut
down the solenoid supply, but the failure is severe
enough that the TCM places the transmission into a
predefined gear, there are several shift performanceconcerns. For instance, if the transmission is slip-
ping, the controller tries to place the transmission
into 3rd gear and maintain 3rd gear for all forward
drive conditions.STANDARD PROCEDURE - TCM ADAPTATION
The adaptation procedure requires the use of the
DRBIIItscan tool. This program allows the elec-
tronic transmission system to re-calibrate itself. This
will provide the proper baseline transmission opera-
tion. The adaptation procedure should be performed
if any of the following procedures are performed:
²Transmission Assembly Replacement
²Transmission Control Module Replacement
²Clutch Plate and/or Seal Replacement
²Electrohydraulic Unit Replacement or Recondi-
tion
(1) With the DRBIIIt, reset the Transmission
adaptives. Resetting the adaptives will set the adap-
tives to factory settings.
NOTE: Perform the Coast Down Adaptations first.
The Transmission Temperature must be greater
than 60ÉC (140ÉF) and less than 70ÉC (158ÉF). Fail-
ure to stay within these temperature ranges will
void the procedure.
(2) Drive the vehicle until the transmission tem-
perature is in the specified range.
(3) Perform 4 to 5 coast downs from 5th to 4th
gear and then 4th to 3rd gear.
NOTE: For Upshift adaptation, the Transmission
temperature must be greater than 60ÉC (140ÉF) and
less than 100ÉC (212ÉF). Failure to stay within these
temperature ranges will void this procedure.
(4) From a stop, moderately accelerate the vehicle
and obtain all forward gear ranges while keeping the
Engine RPM below 1800 RPM. Repeat this procedure
4 to 5 times.
(5) Obtaining 5th gear may be difficult at 1800
RPM. Allow the transmission to shift into 5th gear at
a higher RPM then lower the RPM to 1800 and per-
form manual shifts between 4th and 5th gears using
the shift lever.
(6) The TCM will store the adaptives every 10
minutes. After completion of the adaptation proce-
dure make sure the vehicle stays running for at least
10 minutes.
(7) It is possible to manually store the adaptives
under the 10 minute time frame using the DRBIIIt
Store Adaptives procedure.
8E - 8 ELECTRONIC CONTROL MODULESVA
TRANSMISSION CONTROL MODULE (Continued)