TABLE OF CONTENTS - Continued
FLAME SENSOR SHORTED..............................................91
GLOW PIN OPEN.......................................................91
GLOW PIN SHORTED...................................................91
HEATER IN LOCKOUT MODE.............................................93
HEATER OVERHEATED..................................................93
SUCCESSIVE OVERHEATING............................................93
OVER VOLTAGE........................................................96
OVERHEATING SENSOR OPEN...........................................97
OVERHEATING SENSOR SHORTED.......................................97
TEMP SENSOR OPEN...................................................98
TEMP SENSOR SHORTED...............................................98
UNDER VOLTAGE......................................................99
COMMUNICATION
*NO RESPONSE FROM AIRBAG CONTROL MODULE.......................102
*NO RESPONSE FROM AUTOMATIC TEMPERATURE CONTROL..............104
*NO RESPONSE FROM CABIN HEATER MODULE..........................106
*NO RESPONSE FROM CENTRAL TIMER MODULE.........................108
*NO RESPONSE FROM CONTROLLER ANTILOCK BRAKE...................110
*NO RESPONSE FROM ENGINE CONTROL MODULE.......................112
*NO RESPONSE FROM HEATER BOOSTER MODULE.......................114
*NO RESPONSE FROM INSTRUMENT CLUSTER...........................116
*NO RESPONSE FROM RADIO..........................................118
*NO RESPONSE FROM SECURITY SYSTEM MODULE......................120
*NO RESPONSE FROM SENTRY KEY REMOTE ENTRY MODULE.............122
*NO RESPONSE FROM SHIFTER ASSEMBLY..............................124
*NO RESPONSE FROM TRANSMISSION CONTROL MODULE................126
HEATING & A/C
A/C COMPRESSOR CONTROL HIGH OR OPEN (ACTIVE)....................128
A/C COMPRESSOR CONTROL HIGH OR OPEN (STORED)...................130
A/C COMPRESSOR CONTROL SHORTED LOW (STORED)...................130
AIR OUTLET TEMP SENSOR HIGH OR OPEN (STORED)....................130
AIR OUTLET TEMP SENSOR SHORTED LOW (STORED)....................130
AUX FAN RELAY CONTROL HIGH OR OPEN (STORED).....................130
AUX FAN RELAY CONTROL SHORTED LOW (STORED).....................130
BLOWER STAGE 1 HIGH OR OPEN (STORED).............................130
BLOWER STAGE 1 SHORTED LOW (STORED).............................130
CABIN HEATER CONTROL HIGH OR OPEN (STORED)......................130
CABIN HEATER CONTROL SHORTED LOW (STORED)......................130
CIRC PUMP CONTROL HIGH OR OPEN (STORED).........................130
CIRC PUMP CONTROL SHORTED LOW (STORED).........................130
EVAP TEMP SENSOR HIGH OR OPEN (STORED)..........................130
EVAP TEMP SENSOR SHORTED LOW (STORED)..........................130
NO COMMUNICATION BUS (STORED)....................................130
NO COMMUNICATION WITH ECM (STORED)..............................130
NO COMMUNICATION WITH IC (STORED).................................130
RECIRC AIR SOLENOID CONTROL HIGH OR OPEN (STORED)...............130
RECIRC AIR SOLENOID CONTROL SHORTED LOW (STORED)...............130
REFRIG PRESS SENSOR HIGH OR OPEN (STORED).......................130
REFRIG PRESS SENSOR SHORTED LOW (STORED).......................130
WATER CYCLE VALVE CONTROL HIGH OR OPEN (STORED)................130
WATER CYCLE VALVE CONTROL SHORTED LOW (STORED)................130
iii
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
loads are connected to cables and mounted in a
storage case. The cables can be directly connected to
some airbag system connectors. Jumpers are used
to convert the load tool cable connectors to the other
airbag system connectors. The adapters are con-
nected to the module harness connector to open
shorting clips and protect the connector terminal
during testing. When using the load tool follow all of
the safety procedures in the service information for
disconnecting airbag system components. Inspect
the wiring, connector and terminals for damage or
misalignment. Substitute the airbag load tool in
place of a Driver or Passenger Airbag, seat belt
tensioner, clockspring (use a jumper if needed).
Then follow all of the safety procedures in the
service information for connecting airbag system
components. Read the module active DTCs. If the
module reports NO ACTIVE DTCs the defective
components has been removed from the system and
should be replaced. If the DTC is still active, con-
tinue this process until all components in the circuit
have been tested. Then disconnect the module con-
nector and connect the matching adapter to the
module connector. With all airbags disconnected
and the adapter installed the squib wiring can be
tested for open and shorted conditions.
3.1.6 DIAGNOSTIC TROUBLE CODES
Airbag diagnostic trouble codes consist of active
and stored codes. If more than one code exists,
diagnostic priority should be given to the active
codes. Each diagnostic trouble code is diagnosed by
following a specific testing procedure. The diagnos-
tic test procedures contain step-by-step instructions
for determining the cause of the trouble codes. It is
not necessary to perform all of the tests in this book
to diagnose an individual code. Always begin by
reading the diagnostic trouble codes with the
DRBIIIt. This will direct you to the specific test(s)
that must be performed. In certain test procedures
within this manual, diagnostic trouble codes are
used as a diagnostic tool.
3.1.6.1 ACTIVE CODES
If the lamp remains on, there could be an active
DTC in the system. The code becomes active as soon
as the malfunction is detected or key-on, whichever
occurs first. An active trouble code indicates an
on-going malfunction. This means that the defect is
currently there every time the airbag control mod-
ule checks that circuit or component. Some DTCs,
Internal Module and squib DTCs, will keep the
indicator illuminated even if they are no longer
active. If the lamp is on and no active codes are
present, cycling the ignition switch off and then on
will refresh the lamp state. It is impossible to erase
an active code.
3.1.6.2 STORED CODES
Airbag codes are automatically stored in the
ACM's memory as soon as the malfunction is de-
tected. A stored code indicates there was an active
code present at some time. Stored diagnostic trou-
ble code will remain stored until erased by the DRB.
If a malfunction is not active while performing a
diagnostic test procedure, the active code diagnostic
test will not locate the source of the problem. In this
case, the stored code can indicate an area to inspect.
Maintain a safe distance from all airbags while
performing the following inspection. If no obvious
problems are found, erase stored codes, and with
the ignition on wiggle the wire harness and connec-
tors, rotate the steering wheel from stop to stop.
Recheck for codes periodically as you work through
the system. This procedure may uncover a malfunc-
tion that is difficult to locate.
3.2 COMMUNICATION
3.2.1 COMMUNICATION K-LINES
The K-Lines are a group of circuits that connect
each control module to the Data Link Connector
(DLC). Each control module is connected to the DLC
with a single K-Line. The DRBIIItuses the K-Line
to communicate with each control module. With the
use of the K-Lines the DRBIIItis able to read each
control modules DTCs, sensor displays, I/Os etc. If
DRBIIItcommunications with a particular control
module is lost, one of the possible causes could be a
fault in the module's K-Line.
NOTE: It is important to note the DRBIIIT
uses the K-Lines for diagnostic and
monitoring functions and is no way
connected to the CAN data bus network.
The following modules that use the K-line on this
vehicle are:
²Airbag Control Module (ACM)
²Automatic Temperature Control (ATC)
²Cabin Heater Module (CHM)
²Central Timer Module (CTM)
²Controller Antilock Brake (CAB)
²Engine Control Module (ECM)
²Heater Booster Module (HBM)
²Instrument Cluster (IC)
²Shifter Assembly (SA)
²Security System Module (SSM)
²Sentry Key Remote Entry Module (SKREEM)
²Transmission Control Module (TCM)
4
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
WARNING:REASSEMBLE ALL COMPONENTS
BEFORE ROAD TESTING A VEHICLE. DO NOT
TRY TO READ THE DRBIIITSCREEN OR
OTHER TEST EQUIPMENT DURING A TEST
DRIVE. DO NOT HANG THE DRBIIITOR OTHER
TEST EQUIPMENT FROM THE REARVIEW
MIRROR DURING A TEST DRIVE. HAVE AN
ASSISTANT AVAILABLE TO OPERATE THE
DRBIIITOR OTHER TEST EQUIPMENT.
FAILURE TO FOLLOW THESE INSTRUCTIONS
CAN RESULT IN PERSONAL INJURY OR
DEATH.
5.0 REQUIRED TOOLS AND
EQUIPMENT
DRBIIIt(diagnostic read-out box)
Jumper wires
Ohmmeter
Voltmeter
Test Light
8310 Airbag System Load Tool
8443 SRS Airbag System Load Tool
9001 R F Detector
6.0 GLOSSARY OF TERMS
ABSantilock brake system
ACMairbag control module
ACTactuator
AECMairbag electronic control module
(ACM)
ASDMairbag system diagnostic module
(ACM)
AT Cautomatic temperature control
CABcontroller antilock bake
CANcontroller area network
CHMcabin heater module
CPAconnector positive assurance
CTMcentral timer module
DABdriver airbag
DCHAdiesel cabin heater assist (cabin
heater)
DLCdata link connector
DTCdiagnostic trouble code
DRdriver
EBLelectric back lite (rear window de
fogger)
ECMengine control module
GCCGulf Coast Countries
HBMheater booster module
HVACheater ventilation, air conditioning
ICinstrument cluster
MICmechanical instrument cluster
RSMRain Sensor Module
SAshifter assembly
SKREEMsentry key remote entry module
SSMsecurity system module
TCMtransmission control module
13
GENERAL INFORMATION
CLOCKSPRING C2 - YELLOWCAV CIRCUIT FUNCTION
1 20VT DRIVER AIRBAG SQUIB 1 LINE 1
2 20DG DRIVER AIRBAG SQUIB 1 LINE 2
CONTROLLER ANTILOCK BRAKECAV CIRCUIT FUNCTION
1 12BR GROUND
2 12RD FUSED B(+)
3- -
4- -
5 14BR GROUND
6 14RD FUSED B(+)
7- -
8 20BK/DG SENSOR SIGNAL
9 20YL/WT SENSOR SIGNAL
10 20YL/RD SENSOR SIGNAL
11 18BL/BK K-ABS/SHIFTER ASSEMBLY
12 18BK LEFT FRONT WHEEL SPEED SENSOR (+)
13 - -
14 20WT LEFT REAR WHEEL SPEED SENSOR (+)
15 18BR RIGHT FRONT WHEEL SPEED SENSOR (-)
16 18BK RIGHT FRONT WHEEL SPEED SENSOR (+)
17 - -
18 - -
19 - -
20 20WT BRAKE SWITCH OUTPUT
21 20BR GROUND
22 - -
23 18BK/RD FUSED OPTIONAL EQUIPMENT RELAY OUTPUT
24 20DG/WT CAN C BUS (+)
25 20BR SENSOR GROUND
26 20WT/GY BRAKE PRESSURE SENSOR SIGNAL
27 18BK/BL TCS SWITCH (ASR) SENSE
28 18BR LEFT FRONT WHEEL SPEED SENSOR (-)
29 20BR LEFT REAR WHEEL SPEED SENSOR (-)
30 20BR RIGHT REAR WHEEL SPEED SENSOR (-)
31 20YL RIGHT REAR WHEEL SPEED SENSOR (+)
32 18BK/RD BRAKE LAMP SWITCH OUTPUT
33 - -
34 - -
35 - -
36 - -
37 - -
38 - -
39 20RD/BL POWER INPUT
40 20DG CAN C BUS (-)
41 20DG/YL SENSOR SIGNAL
42 20WT/RD 5 VOLT SUPPLY
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CONNECTOR PINOUTS
INSTRUMENT CLUSTER C1CAV CIRCUIT FUNCTION
1 20BR FUEL LEVEL SENSOR SIGNAL RETURN
2 20BR/DG AMBIENT TEMPERATURE SENSOR SIGNAL RETURN
4 20WT/GY K-IC/ATC/HBM/CHM
5 20BR/BK PARK BRAKE INDICATOR SIGNAL
7 20BK/DG RIGHT TURN SIGNAL
10 20BL/BK FUEL LEVEL SENSOR SIGNAL (+)
11 20BL/DG AMBIENT TEMPERATURE SENSOR SIGNAL (+)
14 20DG/WT/BL ENGINE COOLANT LEVEL SWITCH SIGNAL
15 20BR/WT FRONT COURTESY LAMPS CONTROL
16 20YL/RD SEAT BELT SWITCH SIGNAL
17 20DG CAN C BUS (-)
18 20DG/WT CAN C BUS (+)
INSTRUMENT CLUSTER C2 - WHITECAV CIRCUIT FUNCTION
1- -
2- -
3 20RD/YL FUSED B(+)
4 20BR/WT BRAKE WEAR SENSOR SIGNAL
5- -
6 18BR GROUND
7 20GY/DG/RD LAMP DRIVER
8 20BL/WT FUSED HIGH BEAM SWITCH OUTPUT
9 20BL/RD/WT VEHICLE SPEED SENSOR OUTPUT
10 20BK FUSED IGNITION SWITCH OUTPUT (RUN-START)
11 20BL/BK KEY-IN IGNITION SWITCH SIGNAL
12 - -
13 20BK/WT LEFT TURN SIGNAL
14 20BR/YL BRAKE FLUID LEVEL INDICATOR SIGNAL
15 20BL GENERATOR FIELD DRIVER
16 20YL AIRBAG WARNING INDICATOR DRIVER
17 - -
18 20BL/VT D(+) RELAY NO. 1 CONTROL
18 20BL/VT D(+) RELAY NO. 1 CONTROL
INTRUSION SENSOR NO. 1 - BLACKCAV CIRCUIT FUNCTION
1 20BR GROUND
2 20DG/BK INTRUSION SENSOR 1 SIGNAL
3 20DG/YL INTRUSION SENSOR INTERFACE
4 20RD/DG FUSED B(+)
INTRUSION SENSOR NO. 2 - BLACKCAV CIRCUIT FUNCTION
1 20BR GROUND
2 20GY/BK INTRUSION SENSOR 2 SIGNAL
3 20DG/YL INTRUSION SENSOR INTERFACE
4 20RD/DG FUSED B(+)
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279
CONNECTOR PINOUTS
SECURITY SYSTEM MODULE C2 - LT. GREENCAV CIRCUIT FUNCTION
1 16DG/YL INTRUSION SENSOR INTERFACE
2 16GY/BL WINDOW DEFOGGER-LEFT REAR OUTPUT
3 16GY WINDOW DEFOGGER RELAY-RIGHT REAR OUTPUT
4 20DG/BK INTRUSION SENSOR 1 SIGNAL
5- -
6- -
7 20GY/BK INTRUSION SENSOR 2 SIGNAL
8 16GY/DG K-CTM/SSM
9 18BK/BL SIREN SIGNAL CONTROL
10 20DG/WT/BL INTRUSION SENSOR 3 SIGNAL
11 16WT/BL RKE INTERFACE
12 16WT/BL/RD SECURITY SYSTEM INTERFACE
SENTRY KEY REMOTE ENTRY MODULE (SKREEM)CAV CIRCUIT FUNCTION
1 18YL RKE ANTENNA
2 16BR GROUND
3 16RD/YL FUSED B(+)
4 16BK/WT LEFT TURN SIGNAL
5 20DG/WT CAN C BUS (+)
6 20DG CAN C BUS (-)
7 16BK/YL FUSED IGNITION SWITCH OUTPUT (RUN-START)
8 20WT/DG K-SKREEM
9 16WT/BL/RD (EXCEPT
VTSS)RKE INTERFACE
9 16WT/BL/RD (VTSS) SECURITY SYSTEM INTERFACE
10 18DG/YL TURN SIGNAL/ANTI-THEFT ALARM RELAY-LEFT/RIGHT CONTROL
11 20BR TRANSPONDER COIL (+)
12 - TRANSPONDER COIL (-)
SHIFTER ASSEMBLY - BLACKCAV CIRCUIT FUNCTION
1- -
2 20GY/DG/RD LAMP DRIVER
3 20BL/DG K-ABS/SHIFTER ASSEMBLY
4 18BR GROUND
5 20BK/BL/RD BRAKE LAMP SWITCH
6 20DG/WT CAN C BUS (+)
7 20DG CAN C BUS (-)
8 18BK/DG TRANSMISSION RELAY OUTPUT
9 16WT/BL/RD FUSED IGNITION SWITCH OUTPUT (RUN-START)
10 16WT/RD BACK-UP LAMP
SIREN - BLACKCAV CIRCUIT FUNCTION
1 18RD/DG FUSED B(+)
2 18BR GROUND
3 18BK/BL SIREN SIGNAL CONTROL
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CONNECTOR PINOUTS