TEST ACTION APPLICABILITY
2WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNI-
TION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BE-
FORE PROCEEDING.
Disconnect the Driver Airbag Squib connector(s).
NOTE: Check connectors - Clean and repair as necessary.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, DO NOT PLACE AN
INTACT UNDEPLOYED AIRBAG FACE DOWN ON A HARD SURFACE, THE
AIRBAG WILL PROPEL INTO THE AIR IF ACCIDENTALLY DEPLOYED.
Connect the appropriate Load Tool to the Driver Airbag connector(s).
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNI-
TION ON, THEN RECONNECT THE BATTERY.
With the DRBIIIt, read the active Airbag Control Module DTC's.
Does the DRBIIItshow DRIVER SQUIB 1 SHORT TO GROUND?All
Ye s!Go To 3
No!Replace the Driver Airbag in accordance with the Service Infor-
mation.
Perform AIRBAG VERIFICATION TEST - VER 1.
3WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNI-
TION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BE-
FORE PROCEEDING.
Disconnect the Load Tool from the Driver Airbag connector(s).
Disconnect the Clockspring connector.
NOTE: Check connectors - Clean and repair as necessary.
Connect the appropriate Load Tool to the Clockspring connector.
WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNI-
TION ON, THEN RECONNECT THE BATTERY.
With the DRBIIIt, read the active Airbag Control Module DTC's.
Does the DRBIIItshow DRIVER SQUIB 1 SHORT TO GROUND?All
Ye s!Go To 4
No!Replace the Clockspring in accordance with the Service Informa-
tion.
Perform AIRBAG VERIFICATION TEST - VER 1.
4WARNING: TO AVOID PERSONAL INJURY OR DEATH, TURN THE IGNI-
TION OFF, DISCONNECT THE BATTERY AND WAIT TWO MINUTES BE-
FORE PROCEEDING.
Disconnect the Load Tool from the Clockspring connector.
Disconnect the Airbag Control Module connector(s).
NOTE: Check connectors - Clean and repair as necessary.
Connect the appropriate Load Tool Adaptor to the Airbag Control Module connector.
Measure the resistance of the Driver Squib 1 Line 1 and Line 2 circuits between
Clockspring connector and ground.
Is the resistance below 10K ohms on either circuit?All
Ye s!Repair Driver Squib 1 Line 1 or Line 2 circuits shorted to ground.
Perform AIRBAG VERIFICATION TEST - VER 1.
No!Go To 5
43
AIRBAG
DRIVER SQUIB 1 SHORT TO GROUND ÐContinued
TEST ACTION APPLICABILITY
2WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
NOTE: The heater's control unit will store up to five DTCs in its memory.
NOTE: If the heater's control unit detects a new fault in the system, one that
is not already stored in its memory, it will clear the oldest of the five stored
DTCs, and it will store the new fault's DTC.
NOTE: If the heater's control unit detects a reoccurrence of a stored fault,
it will overwrite that fault's DTC with the most recent occurrence.
Turn the ignition on.
Verify that the Cabin Heater or Heater Booster is switched off.
Set the blend control to the max heat position and the mode control to the floor
position.
With the DRBIIIt, record and erase the Cabin Heater or Heater Booster Module's
DTCs.
Start the engine. Allow the engine to idle.
With the DRBIIIt, monitor for Cabin Heater Module or Heater Booster Module DTCs
while performing the following step.
NOTE: Do not disconnect the vehicle's battery or the heater's main power
supply while the heater is in operation or in run-down mode. Failure to
follow these instructions can result in excess emissions from the heater
during heater operation.
Switch the Cabin Heater or Heater Booster on. If operable, allow the heater to run
through at least one cycle of operation (approximately 10 minutes), and then switch
the heater off.
Does the DRBIIItdisplay any DTCs?All
Ye s!If the Heater In Lockout Mode DTC is present, record and erase
DTCs before performing any diagnostic procedures. Return to the
symptom list and choose the symptom(s).
Perform HEATER VERIFICATION TEST - VER 1.
No!Go To 3
70
CABIN HEATER
A. HEATER PRE-TEST ÐContinued
Symptom List:
HEATER IN LOCKOUT MODE
HEATER OVERHEATED
SUCCESSIVE OVERHEATING
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be HEATER IN LOCKOUT MODE.
When Monitored and Set Condition:
HEATER IN LOCKOUT MODE
When Monitored: During heater activation and operation.
Set Condition: This DTC will set if multiple attempts to start the heater have failed or if
successive overheating occurs.
HEATER OVERHEATED
When Monitored: After heater activation, when the system is in a steady state of
operation.
Set Condition: This DTC will set if the Temperature Sensor's resistance or Overheating
Sensor's resistance is not within the expected parameters (coolant temperature in the
heater module exceeds 105ÉC [221ÉF]).
SUCCESSIVE OVERHEATING
When Monitored: After heater activation, when the system is in a steady state of
operation.
Set Condition: This DTC will set if successive overheating occurs.
POSSIBLE CAUSES
CABIN HEATER ASSEMBLY OR HEATER BOOSTER ASSEMBLY
HEATER'S COOLANT HOSES RESTRICTED/LEAKING/DAMAGED
ENGINE'S COOLING SYSTEM FAULT
CABIN HEATER OR HEATER BOOSTER CONTROL UNIT
HEATER OVERHEATED/SUCCESSIVE OVERHEATING CLEARED, ADDITIONAL DTC(S)
PRESENT
93
CABIN HEATER
TEST ACTION APPLICABILITY
1WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
CAUTION: DO NOT PERFORM THIS TEST UNLESS DIRECTED HERE BY
THE HEATER PRE-TEST. ALWAYS PERFORM THE HEATER PRE-TEST
PRIOR TO PERFORMING ANY OTHER TEST FOR THE RESULT TO BE
VALID.
Turn the ignition off.
NOTE: If there is an internal leak in the heater, a continuous loud chunking
or grinding noise may have been heard coming from the assembly during
the Pre-test.
Check for engine coolant continuously flowing out of the heater's exhaust pipe.
Is engine coolant coming out of the heater's exhaust pipe?All
Ye s!Replace the Cabin Heater Assembly or Heater Booster Assembly
in accordance with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
No!Go To 2
2WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
WARNING: ALLOW THE HEATER ASSEMBLY TO COOL BEFORE PER-
FORMING A COMPONENT INSPECTION/REPAIR/REPLACEMENT. FAIL-
URE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL
INJURY OR DEATH.
Turn the ignition off.
Inspect the heater's coolant hoses for restrictions, leakage, and damage.
Are the heater's coolant hoses Ok?All
Ye s!Go To 3
No!Repair the heater's coolant hoses as necessary in accordance with
the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
3WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
Check that the engine's cooling system is operating properly in accordance with the
Service Information.
Is the engine's cooling system operating properly?All
Ye s!Go To 4
No!Repair the engine's cooling system in accordance with the Service
Information.
Perform HEATER VERIFICATION TEST - VER 1.
94
CABIN HEATER
HEATER IN LOCKOUT MODE ÐContinued
TEST ACTION APPLICABILITY
4WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
Refill the cooling system in accordance with the Service Information.
Start the engine.
Allow the engine to reach normal operating temperature.
Turn the engine off.
Allow the engine coolant to cool down to a temperature of 50ÉC (122ÉF).
Start the engine.
Allow the engine to reach normal operating temperature.
Turn the engine off.
View repairAll
Repair
Go To 5
5WARNING: NEVER OPERATE THE HEATER IN AN ENCLOSED AREA
THAT DOES NOT HAVE EXHAUST VENTILATION FACILITIES. ALWAYS
VENT THE EXHAUST WHEN OPERATING THE HEATER. FAILURE TO
FOLLOW THESE INSTRUCTIONS CAN RESULT IN PERSONAL INJURY
OR DEATH.
NOTE: The heater's control unit will store up to five DTCs in its memory.
NOTE: If the heater's control unit detects a new fault in the system, one that
is not already stored in its memory, it will clear the oldest of the five stored
DTCs, and it will store the new fault's DTC.
NOTE: If the heater's control unit detects a reoccurrence of a stored fault,
it will overwrite that fault's DTC with the most recent occurrence.
Turn the ignition on.
Verify that the Cabin Heater or Heater Booster is switched off.
Set the blend control to the max heat position and the mode control to the floor
position.
Start the engine. Allow the engine to idle.
With the DRBIII, monitor for Cabin Heater or Heater Booster Module DTCs while
performing the following step.
NOTE: Do not disconnect the vehicle's battery or the heater's main power
supply while the heater is in operation or in run-down mode. Failure to
follow these instructions can result in excess emissions from the heater
during heater operation.
Switch the Cabin Heater or Heater Booster on. If necessary, allow the heater to run
through at least one cycle of operation (approximately 10 minutes), and then turn the
heater off.
Turn the engine off.
Does the DRBIIItdisplay any DTCs?All
Overheating Related DTC(s) Reset
Replace the Cabin Heater Assembly or Heater Booster Assembly
in accordance with the Service Information.
Perform HEATER VERIFICATION TEST - VER 1.
Ovrheatng DTC(s) clear, Other DTC(s) Set
Return to the symptom list and choose the symptom(s).
Perform HEATER VERIFICATION TEST - VER 1.
No DTCs Present
Test Complete.
95
CABIN HEATER
HEATER IN LOCKOUT MODE ÐContinued
Symptom:
*NO RESPONSE FROM CONTROLLER ANTILOCK BRAKE
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE CONTROLLER ANTILOCK BRAKE
SHIFTER ASSEMBLY
K-ABS, SHIFTER ASSEMBLY CIRCUIT SHORTED TO GROUND
SHIFTER ASSEMBLY
K-ABS, SHIFTER ASSEMBLY CIRCUIT SHORTED TO VOLTAGE
K-ABS, SHIFTER ASSEMBLY CIRCUIT OPEN
CONTROLLER ANTILOCK BRAKE
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Controller Antilock Brake harness connector.
Check each power and ground circuit to the module.
Were any problems found?All
Ye s!Refer to the wiring diagrams located in the service information to
help isolate an open or shorted condition. Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition off.
Disconnect the CAB harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-ABS, Shifter Assembly circuit.
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Go To 4
3 Turn the ignition off.
Disconnect the Shifter Assembly harness connector.
Measure the resistance between ground and the K-ABS, Shifter Assembly circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the K-ABS, Shifter Assembly circuit for a short to ground.
Perform ABS VERIFICATION TEST - VER 1.
No!Replace the Shifter Assembly in accordance with the service
information.
Perform ABS VERIFICATION TEST - VER 1.
11 0
COMMUNICATION
TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the DRBIIItfrom the DLC.
Disconnect the CAB harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-ABS, Shifter Assembly
circuit.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Go To 5
No!Go To 6
5 Turn the ignition off.
Disconnect the Shifter Assembly harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the K-ABS, Shifter Assembly
circuit.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s!Repair the K-ABS, Shifter Assembly circuit for a short to voltage.
Perform ABS VERIFICATION TEST - VER 1.
No!Replace the Shifter Assembly in accordance with the service
information.
Perform ABS VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the CAB harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance of the K-ABS, Shifter Assembly circuit between the CAB
connector and the DLC.
Is the resistance below 5.0 ohms?All
Ye s!Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.
No!Repair the K-ABS, Shifter Assembly circuit for an open.
Perform ABS VERIFICATION TEST - VER 1.
111
COMMUNICATION
*NO RESPONSE FROM CONTROLLER ANTILOCK BRAKE ÐContinued
Symptom:
*NO RESPONSE FROM SHIFTER ASSEMBLY
POSSIBLE CAUSES
CHECK POWERS AND GROUNDS TO THE SHIFTER ASSEMBLY
CONTROLLER ANTILOCK BRAKE
K-ABS, SHIFTER ASSEMBLY CIRCUIT SHORTED TO GROUND
CONTROLLER ANTILOCK BRAKE
K-ABS, SHIFTER ASSEMBLY CIRCUIT SHORTED TO VOLTAGE
K-ABS, SHIFTER ASSEMBLY CIRCUIT OPEN
SHIFTER ASSEMBLY
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Shifter Assembly harness connector.
Check each power and ground circuit to the module.
Were any problems found?All
Ye s!Refer to the wiring diagrams located in the service information to
help isolate an open or shorted condition. Repair as necessary.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Go To 2
2 Turn the ignition off.
Disconnect the Shifter Assembly harness connector.
Disconnect the DRBIIItfrom the DLC.
Measure the resistance between ground and the K-ABS, Shifter Assembly circuit.
Is the resistance below 5.0 ohms?All
Ye s!Go To 3
No!Go To 4
3 Turn the ignition off.
Disconnect the CAB harness connector.
Measure the resistance between ground and the K-ABS, Shifter Assembly circuit.
Is the resistance below 5.0 ohms?All
Ye s!Repair the K-ABS, Shifter Assembly circuit for a short to ground.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
No!Replace the Controller Antilock Brake in accordance with the
service information.
Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1.
124
COMMUNICATION