door lock MERCEDES-BENZ SPRINTER 2006 Service Manual

TABLE OF CONTENTS
1.0 INTRODUCTION.........................................................1
1.1SYSTEM COVERAGE...............................................1
1.2SIX-STEP TROUBLESHOOTING PROCEDURE..........................1
2.0 IDENTIFICATION OF SYSTEM.............................................1
3.0 SYSTEM DESCRIPTION AND FUNCTIONAL OPERATION......................1
3.1AIRBAG SYSTEM...................................................1
3.1.1DRIVER AIRBAG............................................2
3.1.2CLOCKSPRING.............................................3
3.1.3PASSENGER AIRBAG.......................................3
3.1.4SEAT BELT TENSIONERS....................................3
3.1.5SPECIAL TOOLS............................................3
3.1.6DIAGNOSTIC TROUBLE CODES..............................4
3.1.6.1ACTIVE CODES............................................4
3.1.6.2STORED CODES...........................................4
3.2COMMUNICATION..................................................4
3.2.1COMMUNICATION K-LINES..................................4
3.2.2CAN BUS..................................................5
3.3HEATING & A/C SYSTEM............................................5
3.3.1AUTOMATIC TEMPERATURE CONTROL (ATC)..................5
3.3.1.1SYSTEM CONTROLS........................................5
3.3.1.2SYSTEM DIAGNOSTICS.....................................5
3.3.2CABIN HEATER MODULE (CHM) & HEATER BOOSTER MODULE
(HBM).....................................................7
3.3.2.1SYSTEM DESCRIPTION.....................................7
3.3.2.2VENTING THE HEATER'S EXHAUST...........................8
3.3.2.3SYSTEM DIAGNOSTICS.....................................8
3.4INSTRUMENT CLUSTER.............................................9
3.5POWER DOOR LOCKS/RKE..........................................9
3.5.1CENTRAL LOCKING.........................................9
3.5.2REMOTE KEYLESS ENTRY (RKE).............................9
3.5.3AUTO DOOR LOCKS.......................................10
3.5.4ACCIDENT RESPONSE.....................................10
3.6VEHICLE THEFT SECURITY SYSTEM (VTSS)..........................10
3.7USING THE DRBIIIT................................................11
3.8DRBIIITERROR MESSAGES.........................................11
3.9DRBIIITDOES NOT POWER UP (BLANK SCREEN)......................11
3.10DISPLAY IS NOT VISIBLE...........................................11
4.0 DISCLAIMERS, SAFETY, WARNINGS......................................11
4.1DISCLAIMERS.....................................................11
4.2SAFETY..........................................................11
4.2.1TECHNICIAN SAFETY INFORMATION.........................11
4.2.2VEHICLE PREPARATION FOR TESTING.......................12
4.2.3SERVICING SUB-ASSEMBLIES..............................12
4.2.4DRBIIITSAFETY INFORMATION.............................12
4.3WARNINGS.......................................................12
4.3.1VEHICLE DAMAGE WARNINGS..............................12
4.3.2ROAD TESTING A COMPLAINT VEHICLE......................12
i

TABLE OF CONTENTS - Continued
A/C COMPRESSOR CONTROL SHORTED LOW (ACTIVE)....................132
AIR OUTLET TEMP SENSOR HIGH OR OPEN (ACTIVE).....................134
AIR OUTLET TEMP SENSOR SHORTED LOW (ACTIVE).....................136
ATC FUNCTION TEST COOL FAILURE....................................138
ATC FUNCTION TEST FAILURE..........................................138
ATC FUNCTION TEST HEAT FAILURE.....................................138
AUX FAN RELAY CONTROL HIGH OR OPEN (ACTIVE)......................140
AUX FAN RELAY CONTROL SHORTED LOW (ACTIVE)......................142
BLOWER STAGE 1 HIGH OR OPEN (ACTIVE)..............................144
BLOWER STAGE 1 SHORTED LOW (ACTIVE)..............................146
CABIN HEATER CONTROL HIGH OR OPEN (ACTIVE).......................148
CABIN HEATER CONTROL SHORTED LOW (ACTIVE).......................150
CIRC PUMP CONTROL HIGH OR OPEN (ACTIVE)..........................152
CIRC PUMP CONTROL SHORTED LOW (ACTIVE)..........................154
EVAP TEMP SENSOR HIGH OR OPEN (ACTIVE)...........................156
EVAP TEMP SENSOR SHORTED LOW (ACTIVE)...........................158
NO COMMUNICATION BUS (ACTIVE).....................................160
NO COMMUNICATION WITH ECM (ACTIVE)...............................163
NO COMMUNICATION WITH IC (ACTIVE)..................................165
RECIRC AIR SOLENOID CONTROL HIGH OR OPEN (ACTIVE)................167
RECIRC AIR SOLENOID CONTROL SHORTED LOW (ACTIVE)................169
REFRIG PRESS SENSOR HIGH OR OPEN (ACTIVE)........................171
REFRIG PRESS SENSOR SHORTED LOW (ACTIVE)........................173
WATER CYCLE VALVE CONTROL HIGH OR OPEN (ACTIVE).................175
WATER CYCLE VALVE CONTROL SHORTED LOW (ACTIVE).................177
INSTRUMENT CLUSTER
AMBIENT TEMP SENSOR OPEN/SHORT TO BATTERY......................179
AMBIENT TEMP SENSOR SHORT TO GROUND............................181
FUEL LEVEL SENSOR OPEN/SHORT TO BATTERY.........................182
FUEL LEVEL SENSOR SHORT TO GROUND...............................184
INSTRUMENT CLUSTER INTERNAL FAILURE B1043........................185
INSTRUMENT CLUSTER INTERNAL FAILURE B1053........................186
INSTRUMENT CLUSTER OVERVOLTAGE..................................187
NO CAN COMMUNICATION WITH ABS....................................188
NO CAN COMMUNICATION WITH ECM...................................190
NO CAN COMMUNICATION WITH TCM....................................192
PREGLOW INDICATOR LAMP FAILURE...................................194
SRS INDICATOR LAMP FAILURE.........................................195
POWER DOOR LOCKS/RKE
DRIVER DOOR AJAR INDICATOR DRIVER CIRCUIT SHORT TO GROUND......196
PASSENGER DOOR AJAR INDICATOR DRIVER CIRCUIT SHORT TO GROUND .198
REPLACE CONTROL MODULE..........................................200
RKE INTERFACE CIRCUIT SHORT TO GROUND - CTM......................201
RKE INTERFACE CIRCUIT SHORT TO GROUND - SKREEM..................203
RKE INTERFACE CIRCUIT SHORT TO VOLTAGE - CTM.....................205
RKE INTERFACE CIRCUIT SHORT TO VOLTAGE - SKREEM..................206
THE ACM HAS UNLOCKED THE DOORS..................................208
UNKNOWN TROUBLE CODE UNKNOWN DTC TYPE 2......................209
*RKE INOPERATIVE....................................................210
*RKE POOR RANGE...................................................211
iv

TABLE OF CONTENTS - Continued
VEHICLE THEFT/SECURITY
DRIVER CYLINDER LOCK SWITCH CIRCUIT SHORT TO GROUND............212
DRIVER CYLINDER UNLOCK SWITCH CIRCUIT SHORT TO GROUND.........214
FRONT DOOR JAMB SWITCH CIRCUIT SHORT TO GROUND................216
INTERNAL ERROR - SSM...............................................218
TOWING INCLINATION SENSOR BEYOND LIMITS..........................218
TOWING INCLINATION SENSOR VALUE IS INVALID.........................218
TOWING INCLINATION SENSOR VALUE IS MISSING........................218
INTRUSION SENSOR 1 CIRCUIT OPEN/SHORT TO GROUND................220
INTRUSION SENSOR 1 GROUND CIRCUIT OPEN..........................222
INTRUSION SENSOR 2 CIRCUIT OPEN/SHORT TO GROUND................223
INTRUSION SENSOR 2 GROUND CIRCUIT OPEN..........................225
INTRUSION SENSOR 3 CIRCUIT OPEN/SHORT TO GROUND................226
INTRUSION SENSOR 3 GROUND CIRCUIT OPEN..........................228
REAR OR SLIDING DOOR JAMB SWITCH CIRCUIT SHORT TO GROUND......229
RKE INTERFACE CIRCUIT FAILURE - SSM................................231
SECURITY SYSTEM INTERFACE FAILURE - SSM...........................233
SIREN CIRCUIT OPEN/SHORTED TO GROUND............................235
SIREN INTERNAL FAILURE.............................................237
SIREN SIGNAL CONTROL CIRCUIT SHORT TO GROUND....................238
WINDSHIELD WIPER & WASHER
CHECKING THE RAIN SENSOR/WIPER OPERATION........................239
VERIFICATION TESTS
VERIFICATION TESTS..................................................244
8.0 COMPONENT LOCATIONS..............................................249
8.1AIRBAG SYSTEM.................................................249
8.2AIRBAG CONTROL MODULE.......................................249
8.3DRIVER AIRBAG SQUIB...........................................249
8.4CLOCKSPRING..................................................250
8.5SEAT BELT TENSIONER...........................................250
8.6HEATING & A/C...................................................250
8.6.1AUTOMATIC TEMPERATURE CONTROL (ATC) SYSTEM
COMPONENTS...........................................250
8.6.2CABIN HEATER & HEATER BOOSTER SYSTEM COMPONENTS .251
8.6.3AUTO TEMP CONTROL, CABIN HEATER, & HEATER BOOSTER
FUSES & RELAYS........................................251
8.6.4EVAP TEMP SENSOR & AIR OUTLET TEMP SENSOR..........251
8.7INSTRUMENT CLUSTER...........................................252
8.7.1AMBIENT TEMPERATURE SENSOR.........................252
8.8POWER DOOR LOCKS/RKE........................................252
8.8.1CENTRAL TIMER MODULE.................................252
8.8.2SENTRY KEY REMOTE ENTRY MODULE.....................253
8.8.3DOOR LOCK MOTOR/AJAR SWITCH........................253
8.8.4CONTACT PLATES........................................253
8.8.5DOOR LOCK MOTOR/AJAR SWITCH CONNECTORS...........254
v

TABLE OF CONTENTS - Continued
8.9VEHICLE THEFT SECURITY SYSTEM................................254
8.9.1SECURITY SYSTEM MODULE..............................254
8.9.2INTRUSION SENSORS....................................254
8.9.3SWITCHES..............................................255
8.9.4SIREN..................................................255
9.0 CONNECTOR PINOUTS................................................257
A/C AUXILIARY FAN....................................................257
AIR OUTLET TEMPERATURE SENSOR...................................257
AIRBAG CONTROL MODULE - YELLOW...................................257
AIRBAG SQUIB-DRIVER - YELLOW.......................................258
AIRBAG SQUIB-PASSENGER - YELLOW..................................258
AMBIENT TEMPERATURE SENSOR......................................258
AUTOMATIC TEMPERATURE CONTROL MODULE C1 - BROWN..............259
AUTOMATIC TEMPERATURE CONTROL MODULE C2.......................259
AUXILIARY HEATER CONTROL..........................................259
BLOWER MOTOR RESISTOR BLOCK.....................................259
BLOWER MOTOR-FRONT - BLACK.......................................260
C205 - YELLOW (DASH SIDE)...........................................260
C205 - YELLOW (MAIN BODY SIDE)......................................260
CENTRAL TIMER MODULE C1 - PINK.....................................260
CENTRAL TIMER MODULE C2 - LT. GREEN...............................261
CIRCULATION PUMP (CABIN HEATER MODULE)...........................261
CIRCULATION PUMP (REST SYSTEM)....................................261
CIRCULATION PUMP DIODE............................................261
CLOCKSPRING C2 - YELLOW...........................................262
CONTROLLER ANTILOCK BRAKE........................................262
CYLINDER LOCK SWITCH-DRIVER.......................................263
DATA LINK CONNECTOR - BLACK........................................263
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-DRIVER C1.................263
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-DRIVER C2.................263
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-LEFT SLIDING C1...........263
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-LEFT SLIDING C2...........264
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-PASSENGER C1............264
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-PASSENGER C2............264
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-REAR C1...................264
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-REAR C2...................264
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-RIGHT SLIDING C1..........265
DOOR LOCK MOTOR/AJAR SWITCH ASSEMBLY-RIGHT SLIDING C2..........265
DOSING PUMP........................................................265
ENGINE CONTROL MODULE C1 (EXCEPT OBD) - BLACK...................265
ENGINE CONTROL MODULE C2 (EXCEPT OBD) - BLACK...................266
ENGINE CONTROL MODULE C2 (OBD)...................................267
ENGINE CONTROL MODULE C3 (EXCEPT OBD) - BLACK...................268
EVAPORATOR TEMPERATURE SENSOR..................................269
FUEL LEVEL SENSOR..................................................269
FUSES (FUSE BLOCK NO. 1)............................................271
FUSE BLOCK NO. 1 C1.................................................271
FUSE BLOCK NO. 1 C2.................................................271
FUSE BLOCK NO. 1 C3 - BLACK.........................................272
FUSE BLOCK NO. 1 C4 - BLACK.........................................272
FUSE BLOCK NO. 1 C5 - BLACK.........................................272
vi

TABLE OF CONTENTS - Continued
FUSES (FUSE BLOCK NO. 2)............................................274
FUSES (FUSE BLOCK NO. 3)............................................276
FUSES (FUSE/RELAY BLOCK)...........................................278
HOOD AJAR SWITCH - BLACK...........................................278
HORN (VTSS).........................................................278
IGNITION LOCK SWITCH - BLACK........................................278
INSTRUMENT CLUSTER C1.............................................279
INSTRUMENT CLUSTER C2 - WHITE.....................................279
INTRUSION SENSOR NO. 1 - BLACK.....................................279
INTRUSION SENSOR NO. 2 - BLACK.....................................279
INTRUSION SENSOR NO. 3 - BLACK.....................................280
MASTER DOOR LOCK SWITCH..........................................280
PANIC ALARM SWITCH - BLACK.........................................280
FUSES (PDC).........................................................281
RADIO C1 - BLACK....................................................282
RADIO C2............................................................282
RECIRCULATED AIR SOLENOID VALVE...................................282
REFRIGERANT PRESSURE SENSOR.....................................282
A/C AUXILIARY FAN RELAY (RELAY BLOCK)...............................284
CIRCULATION PUMP RELAY-CABIN HEATER MODULE (RELAY BLOCK).......284
D+ RELAY NO. 2 (RELAY BLOCK)........................................284
FAN STAGE 1 RELAY (RELAY BLOCK)....................................284
OPTIONAL EQUIPMENT RELAY (RELAY BLOCK)...........................284
REMOTE KEYLESS ENTRY ANTENNA....................................284
SEAT BELT SWITCH...................................................284
SEAT BELT TENSIONER-DRIVER - YELLOW...............................285
SEAT BELT TENSIONER-PASSENGER - YELLOW...........................285
SECURITY SYSTEM MODULE C1 - BROWN...............................285
SECURITY SYSTEM MODULE C2 - LT. GREEN.............................286
SENTRY KEY REMOTE ENTRY MODULE (SKREEM)........................286
SHIFTER ASSEMBLY - BLACK...........................................286
SIREN - BLACK.......................................................286
STEERING ANGLE SENSOR............................................287
TOWING/INTRUSION SENSOR ON/OFF SWITCH...........................287
TRANSMISSION CONTROL MODULE C1 - BLACK..........................287
TRANSMISSION CONTROL MODULE C2 - BLACK..........................288
WATER CYCLE VALVE..................................................288
WINDOW DEFOGGER-LEFT REAR.......................................288
WINDOW DEFOGGER-RIGHT REAR......................................288
10.0 SCHEMATIC DIAGRAMS................................................289
10.1AIRBAG SYSTEM.................................................289
10.2COMMUNICATION................................................290
10.2.1COMMUNICATION K-LINES................................290
10.2.2CAN BUS NETWORK......................................291
10.3HEATING & A/C...................................................292
10.3.1AUTOMATIC TEMPERATURE CONTROL (ATC)................292
10.3.2CABIN HEATER MODULE (CHM)............................293
10.3.3HEATER BOOSTER MODULE (HBM).........................294
10.4INSTRUMENT CLUSTER...........................................295
vii

TABLE OF CONTENTS - Continued
10.5POWER DOOR LOCKS/RKE........................................296
10.5.1FRONT DOORS..........................................296
10.5.2SLIDING AND REAR DOORS...............................297
10.5.3SWITCH AND MISCELLANEOUS CIRCUITS...................298
10.6VEHICLE THEFT SECURITY SYSTEM................................299
10.7RAIN SENSOR SYSTEM...........................................300
11.0 CHARTS AND GRAPHS................................................301
11.1EVAP TEMP SENSOR RESISTANCE TO TEMPERATURE
SPECIFICATIONS.................................................301
11.2AIR OUTLET TEMP SENSOR RESISTANCE TO TEMPERATURE
SPECIFICATIONS.................................................301
11.3WIPER SWITCH/WASHER SWITCH VOLTAGE SIGNALS................302
viii

1.0 INTRODUCTION
The procedures contained in this manual include
all the specifications, instructions and graphics
needed to diagnose Sprinter body system problems.
The diagnostics in this manual are based on the
failure condition or symptom being present at the
time of diagnosis.
Please follow the recommendations below when
choosing your diagnostic path.
1. First make sure the DRBIIItis communicating
with the appropriate modules; i.e., if the
DRBIIItdisplays a ``No Response'' or a ``Bus6
Signals Open'' condition, you must diagnose that
first.
2. Read DTC's (diagnostic trouble codes) with the
DRBIIIt.
3. If no DTC's are present, identify the customer
complaint.
4. Once the DTC or customer complaint is identi-
fied, locate the matching test in the Table of
Contents and begin to diagnose the symptom.
All component location views are in Section 8.0.
All connector pinouts are in Section 9.0. All sche-
matics are in Section 10.0. All Charts and Graphs
are in Section 11.0.
An * placed before the symptom description indi-
cates a customer complaint without a DTC.
When repairs are required, refer to the appropri-
ate service information for the proper removal and
repair procedure.
Diagnostic procedures change every year. New
diagnostic systems may be added: carryover sys-
tems may be enhanced. READ THIS MANUAL
BEFORE TRYING TO DIAGNOSE A VEHICLE
DIAGNOSTIC TROUBLE CODE. It is recom-
mended that you review the entire manual to be-
come familiar with all the new and changed diag-
nostic procedures.
This book reflects many suggested changes from
readers of past issues. After using this book, if you
have any comments or suggestions, please fill out
the form in the back of this book and mail it back to
us.
1.1 SYSTEM COVERAGE
This diagnostic procedures manual covers all
Sprinter vehicles.
1.2 SIX-STEP TROUBLESHOOTING
PROCEDURE
Diagnosis of the body system is done in six basic
steps:
²verification of complaint
²verification of any related symptoms
²symptom analysis
²problem isolation
²repair of isolated problem
²verification of proper operation
2.0 IDENTIFICATION OF
SYSTEM
The vehicle systems that are part of the ``body''
system are:
²Airbag
²Automatic Temperature Control
²Communication
²Instrument Cluster
²Power Door Locks/RKE
²Vehicle Theft Security System (VTSS)
²Wiper/Rain Sensor
3.0 SYSTEM DESCRIPTION AND
FUNCTIONAL OPERATION
The body system on the Sprinter consists of a
combination of modules that communicate with
each other using the CAN Bus (controller area
network). Through the CAN Bus, information about
the operation of vehicle components and circuits is
relayed quickly to the appropriate modules. Since
the CAN bus network is for intermodule communi-
cation only, the DRBIIItutilizes K-Lines to estab-
lish communications with each module. It is impor-
tant to note the CAN bus circuits are by no means
tied to the K-Lines. They are completely separate
from each other. For additional information on the
CAN bus and the K-Lines, refer to the Communi-
cation section of this general information.
3.1 AIRBAG SYSTEM
The Sprinter Airbag System contains the follow-
ing components:
²Airbag Control Module (ACM)
²Airbag Warning Indicator (SRS)
²Driver Airbags
²Clockspring
²Passenger Airbag
²Driver Seat Belt Tensioners
²Passenger Seat Belt Tensioners
The Airbag Control Module (ACM) has five major
functions: onboard diagnostics, determine the se-
verity of impacts, squib deployment and Accident
Response, K-Line communications. The ACM is
1
GENERAL INFORMATION

secured to the floor under the Driver seat and
receives power from the Fuse Block No. 1. When-
ever the ignition key is turned to the run or start
position, the ACM performs a system test. The ACM
cannot be repaired or adjusted.
The microprocessor in the ACM monitors the
internal and external airbag system electrical cir-
cuits to determine the system readiness. When a
monitored system is determine to be out of range,
the ACM will set both active and stored diagnostic
trouble codes (DTC). The ACM also contains an
energy-storage capacitor. This capacitor stores
enough electrical energy to deploy the front airbag
components for two seconds following a battery
disconnect or failure during an impact.
The Accelerometer in the ACM is used to sense
the rate of vehicle deceleration, provide verification
of the direction and severity of an impact. When the
preprogrammed conditions are met, the ACM sends
an electrical signal to deploy the appropriate front
airbag system components and a deployment noti-
fication.
To provide an accident response notification, the
ACM is hardwired to the Central Timer module
(CTM) and Engine Control Module (ECM). When a
deployment occurs the ACM provides a 50ms 10.0
volt pulse to the CTM and ECM. When the Accident
Report notification signal is received the CTM un-
locks the door locks and the ECM stalls the engine.
The Accident signal will set a DTC in the CTM and
the door locks will not work until the DTC has been
erased. The ECM will set a DTC if the Accident
Report circuit is shorted to battery voltage. The
ACM saves the deployment record and after three
deployments the ACM must be replaced. The
DRBIIItcan be used to test the Accident Report
Notification feature: select the SYSTEM TEST from
the ACM main menu. Then select the Analog Crash
Output System Test.
The ACM is hardwired to the Instrument Cluster
(MIC) to control Warning Indicator (SRS indicator).
When DTCs becomes activate, the ACM illuminates
the Warning Indicator by pulling the indicator
circuit low. The SRS indicator is the only point at
which the customer can observe symptoms of a
system malfunction.
As part of the system test the ACM illuminates
the Warning Indicator on for 4.0 second bulb test.
After the lamp check, if the indicator turns off, it
means that the ACM has checked the system and
found it to be free of discernible malfunctions.
NON-CRITICAL DTCs
If the lamp comes on and stays on for a period
longer than 4.0 seconds (about 10.0 seconds) is
usually a stored DTC (intermittent problem) in the
system.
CRITICAL DTCs
DTCs that could lead to a condition where the
safety devises may not deploy or incorrectly deploy.
In the event of such a DTC, the safety of the vehicle
occupants can no longer be guaranteed. If the lamp
remains on, there could be an active DTC in the
system. Some DTCs, Internal Module and squib
DTCs, will keep the indicator illuminated even if
the codes are no longer active.
ACM NOT CONFIGURED FOR PASSENGER
AIRBAG AND TENSIONER
If after replacing the ACM the Airbag Warning
Indicator flashes continuously the ACM must be
configured for the Passenger Airbag and Tensioner.
Select Miscellaneous from the ACM main menu and
configure the Passenger Airbag Tensioner squibs.
WARNING:THE AIRBAG SYSTEM IS A
SENSITIVE, COMPLEX ELECTROMECHANICAL
UNIT. BEFORE ATTEMPTING TO DIAGNOSE OR
SERVICE ANY AIRBAG SYSTEM OR RELATED
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENTS YOU MUST
FIRST DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE. WAIT
TWO MINUTES FOR THE SYSTEM CAPACITOR
TO DISCHARGE BEFORE FURTHER SYSTEM
SERVICE. THIS IS THE ONLY SURE WAY TO
DISABLE THE AIRBAG SYSTEM. FAILURE TO
DO THIS COULD RESULT IN ACCIDENTAL
AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, NEVER STRIKE OR KICK THE
AIRBAG CONTROL MODULE, AS IT CAN
DAMAGE THE IMPACT SENSOR OR AFFECT
ITS CALIBRATION.
WARNING: IF AN AIRBAG CONTROL
MODULE IS ACCIDENTALLY DROPPED
DURING SERVICE, THE MODULE MUST BE
SCRAPPED AND REPLACED WITH A NEW
UNIT. FAILURE TO TAKE THE PROPER
PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND
PERSONAL INJURY OR DEATH.
3.1.1 DRIVER AIRBAG
The airbag protective trim cover is the most
visible part of the driver side airbag system. The
airbag is mounted directly to the steering wheel.
Located under the trim cover are the airbag cushion
and the airbag cushion supporting components.
2
GENERAL INFORMATION

3.2.2 CAN BUS
The CAN bus (controller area network) is a data
bus system specifically design for inter module
communication on this vehicle. The CAN bus con-
sists of a special twisted two-core cable. Control
modules are connected to this9twisted pair9. The
CAN bus incorporates two terminating resistors.
One terminator is built into the Engine Control
Module (ECM) and the other is built into the Sentry
Key Remote Entry Module (SKREEM). Each resis-
tor has a value of 120 ohms. The resistor condition
can be confirmed by disconnecting the control mod-
ule and measuring the resistance value at the
appropriate control module pins. This measure-
ment should read 120 ohms. The two CAN circuits,
CAN C Bus (+) and CAN C Bus (-), are bridged by
these two terminating resistors when all control
modules are connected to the bus. These two resis-
tors are connected to the CAN bus network in
parallel. The measurement between the two
twisted CAN circuits, with both the ECM and
SKREEM connected, should measure a value of 60
ohms.
The CAN bus is bi-directional. This means that
each connected control module can send and receive
information. Transmission of data takes place re-
dundantly via both circuits. The data bus levels are
mirrored, meaning that if the binary level on one
circuit is 0, the other circuit transmits binary level
1 and vice versa. The two line concept is used for
two reasons: for fault identification and as a safety
concept.
If a voltage peak occurs on just one circuit, the
receivers can identify this as a fault and ignore the
voltage peak. If a short circuit or interruption
occurs on one of the two CAN circuits, a software-
hardware linked safety concept allows switching to
a single-line operation. The defective CAN circuit is
shut down. A specific data protocol controls how and
when the participants can send and receive.
NOTE: It is important to note the CAN Bus
circuits are used for inter-module
communication only, and is no way
connected to the K-Lines.
The following modules that use the CAN Bus on
this vehicle are:
²Automatic Temperature Control (ATC)
²Controller Antilock Brake (CAB)
²Engine Control Module (ECM)
²Instrument Cluster (IC)
²Sentry Key Remote Entry Module (SKREEM)
²Shifter Assembly (SA)
²Transmission Control Module (TCM)
3.3 HEATING & A/C SYSTEM
3.3.1 AUTOMATIC TEMPERATURE
CONTROL (ATC)
3.3.1.1 SYSTEM CONTROLS
The ATC Module:
²is fully addressable with the DRBIIIt.
IThe DRBIIItcommunicates with the ATC
Module through the Diagnostic Link Connector
(DLC) via a K-Line.
²communicates with other modules over the Con-
troller Area Network (CAN) C Bus.
²controls A/C clutch operation.
²controls EBL operation.
²controls water cycle valve operation.
IThe water cycle valve is a normally open valve,
meaning that it allows full engine coolant flow
through the heater core when no power is
delivered to the valve. The ATC controls the
valve with a pulse width signal. The lower the
percentage of the pulse width signal the more
the valve is open.
²controls Residual Heat Utilization (REST) func-
tion.
²controls blower motor operation, providing four
blower speeds (Low, M1, M2, & High).
²controls recirculation air solenoid valve.
²controls the mode door via cables.
²controls the main power supply to the Heater
Booster (if equipped).
²uses air inlet temperature sensor, air outlet tem-
perature sensor, and evaporator temperature
sensor input, as well as data from other modules
to maintain occupant comfort levels.
3.3.1.2 SYSTEM DIAGNOSTICS
Fault detection is through active and stored Diag-
nostic Trouble Codes (DTCs)
²DTCs are displayed by the DRBIIIt.
²Active DTCs are those which currently exist in
the system. The condition causing the fault must
be repaired in order to clear this type of DTC.
²Stored DTCs are those which occurred in the
system since the ATC Module received the last
9clear diagnostic info9message.
Testing Preparation & Diagnostics
Set the necessary system functions accordingly so
that all of the following prerequisites are met prior
to performing diagnostic tests on the ATC system:
5
GENERAL INFORMATION

Static Heater Signal
A status of9ON9indicates that the heater module
sees the9Stationary Heating Mode ON9signal after
switching on the heater with the heater timer or the
auxiliary heater switch. A status of9OFF9indicates
that the9Stationary Heating Mode ON9signal is
not present at the heater module.
Heater Booster Mode Signal
A status of9ON9indicates that the heater module
sees the9Heater Booster Mode ON9signal after
switching on the heater with the auxiliary heater
switch. A status of9OFF9indicates that the9Heater
Booster Mode ON9signal is not present at the
heater module.
3.4 INSTRUMENT CLUSTER
The Instrument Cluster has easy-to-read instru-
ments, is capable of CAN bus communication and
provides a diagnostic function. The Instrument
Cluster with analog speedometer, tachometer, fuel
and coolant temperature gauges comes in two ver-
sions.
²Speedometer with outer miles-per-hour (mph)
scale and inner kilometers-per-hour (km/h) scale.
Coolant temperature is indicated in Fahrenheit
(for US).
²Speedometer with outer kilometers-per-hour
(km/h) scale and inner miles-per-hours (mph)
scale. Coolant temperature is indicated in de-
grees Celsius (for Canada).
Below the speedometer, there is a LCD multi-
function indicator in clear view of the driver. Warn-
ing and indicator lights (based on colored light
emitting diodes) are located in the bottom of the
instrument cluster with the exception of the turn
signal indicator lights, ASR warning light and re-
serve fuel warning light. The warning lights for the
seat belt usage and parking brake/brake fluid level
are located in the line above the bottom line. The
indicator that illuminates up when the parking
brake is applied or the brake fluid level is low is
different for U.S. and Canada.
When the key is turned to the 2nd position in the
ignition, the function of the following indicator
lights is checked automatically: High Beam ON,
Preheating, airbag malfunction. In case of a broken
LED of the airbag malfunction light, the seat belt
usage warning light will flash for 6 seconds after
the function check is finished. The Instrument
Cluster is operated with the help of 4 buttons
located below the multifunction indicator. The back-
lighting for the instrument cluster uses yellow
LED's and can be adjusted electronically to daylight
and darkness.The instrument cluster includes a warning
buzzer, which sounds (in addition to a warning light
in some cases) when:
²The headlights are on with the ignition off and
the door opened.
²The driver 's seat belt is not fastened with the
ignition on.
²The key is in the ignition and the door is open.
²Critical ASSYST information is displayed in the
multifunction indicator.
3.5 POWER DOOR LOCKS/RKE
3.5.1 CENTRAL LOCKING
The Central Locking System locks all vehicle
doors if any door is locked from the inside or
mechanically locked with the key from the outside.
However, unlocking any door, in that manner, will
only unlock that particular door. The Master Door
Lock Switch on the dash enables the operator to
lock/unlock all doors. By pressing the top of the
rocker type switch once, all doors will lock. Pressing
the switch again will unlock all doors. Pressing the
lower part of the switch once will lock all doors
except the driver door. Pressing the lower part
again will unlock all doors except the driver door. If
the Central Locking System automatically unlocks
after the vehicle was attempted to be locked, at
least one door is not properly closed.
There are two LED indicators in the Master Door
Lock Switch. The left indicator is for the driver door
and the right indicator is for all passenger/cargo
doors. These will indicate if a door is ajar or if the
doors are locked. The door ajar switches are part of
the door lock motor and are mounted in the door
latch assembly.
Inside each door lock motor there is a command
switch. The command switch is operated by the
plunger and signals any change in the lock status,
locked or unlocked. Each command switch is wired
to the Central Timer Module (CTM) sometimes
referred to as the Central Locking Module. If all
doors are closed and are unlocked, and any door is
locked by the key or the interior handle, thereby
changing the command switch, all doors will be
locked. If one of the door lock motors does not reach
the end position after a locking command, it will be
detected by the CTM (command switch not in
9Locked9position) and the vehicle will be unlocked.
3.5.2 REMOTE KEYLESS ENTRY (RKE)
The SKREEM is a combination of the Remote
Keyless Entry Module and the SKIM (Sentry Key
Immobilizer Module). It is located behind the In-
strument Cluster and has an antenna that goes up
9
GENERAL INFORMATION