
TEST ACTION APPLICABILITY
5 Turn the ignition off.
Disconnect the ECM harness connectors.
Disconnect the DRB from the DLC.
Measure the resistance of the SCI Transmit circuit between the ECM connector and
the DLC.
Is the resistance below 5.0 ohms?All
Ye s®Go To 6
No®Repair the SCI Transmit circuit for an open.
Perform ROAD TEST VERIFICATION - VER-2.
6 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Engine Control Module in accordance
with the Service Information.
Perform ROAD TEST VERIFICATION - VER-2.
403
COMMUNICATION
*NO RESPONSE FROM ECM (SCI ONLY) - DIESEL ONLY ÐContinued

TEST ACTION APPLICABILITY
4NOTE: Ensure there is PCI bus communication with other modules. If not,
refer to the PCI Bus Communication Failure symptom and repair as
necessary.
WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING.
Disconnect the Left Side Impact Airbag Control Module harness connector.
Turn the ignition on and then reconnect the Battery.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
With the DRBIIItselect Pep Module Tools.
Select lab scope.
Select Live Data.
Select 12 volt square wave.
Press F2 for Scope, then enter to select channel.
Press F2 and use the down arrow to set voltage range to 20 volts. Press F2 again
when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the Left Side Impact Airbag Control Module connector.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?All
Ye s®Go To 5
No®Repair the PCI Bus circuit for an open.
Perform AIRBAG VERIFICATION TEST - VER 1.
5 If there are no possible causes remaining, view repair. All
Ye s®Replace the Left Side Impact Airbag Control Module (LSIACM) in
accordance with the Service Information. WARNING: Make sure
the battery is disconnected and wait 2 minutes before proceeding.
Perform AIRBAG VERIFICATION TEST - VER 1.
407
COMMUNICATION
*NO RESPONSE FROM LEFT SIACM ÐContinued

TEST ACTION APPLICABILITY
3Note: Ensure there is PCI bus communication with other modules. If not,
refer to the PCI Bus Communication Failure symptom and repair as
necessary.
WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING.
Disconnect the Occupant Restraint Controller harness connector.
Turn the ignition on and then reconnect the Battery.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
With the DRBIIItselect Pep Module Tools.
Select lab scope.
Select Live Data.
Select 12 volt square wave.
Press F2 for Scope, then enter to select channel.
Press F2 and use the down arrow to set voltage range to 20 volts. Press F2 again
when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the Occupant Restraint Controller connector.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?All
Ye s®Go To 4
No®Repair the PCI Bus circuit for an open.
Perform AIRBAG VERIFICATION TEST - VER 1.
4 If there are no possible causes remaining, view repair. All
Repair
Replace the Occupant Restraint Controller (ORC) in accordance
with the Service lnformation. WARNING: Make sure the battery
is disconnected and wait 2 minutes before proceeding.
Perform AIRBAG VERIFICATION TEST - VER 1.
409
COMMUNICATION
*NO RESPONSE FROM ORC ÐContinued

Symptom:
*NO RESPONSE FROM OVERHEAD CONSOLE
POSSIBLE CAUSES
GROUND CIRCUIT OPEN
IGNITION SWITCH OUTPUT CIRCUIT OPEN
FUSED B+ CIRCUIT OPEN
OPEN PCI BUS CIRCUIT
OVERHEAD CONSOLE
TEST ACTION APPLICABILITY
1NOTE: Ensure there is PCI Bus communication with other modules on the
vehicle before proceeding. If not, refer to the symptom list from the menu
and repair as necessary.
Turn the ignition off.
Disconnect the Overhead Console harness connector.
Measure the resistance between ground and the ground circuit (cav 4).
Is the resistance below 5.0 ohms?All
Ye s®Go To 2
No®Repair the ground circuit for an open.
Perform BODY VERIFICATION TEST - VER 1.
2NOTE: Ensure there is PCI Bus communication with other modules on the
vehicle before proceeding. If not, refer to the symptom list from the menu
and repair as necessary.
Turn the ignition off.
Disconnect the Overhead Console harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Ignition Switch Output
circuit.
Is the test light illuminated?All
Ye s®Go To 3
No®Repair the Ignition Switch Output circuit for an open. Refer to the
wiring diagrams located in the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
3NOTE: Ensure there is PCI Bus communication with other modules on the
vehicle before proceeding. If not, refer to the symptom list from the menu
and repair as necessary.
Turn the ignition off.
Disconnect the Overhead Console harness connector.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit.
Is the test light illuminated?All
Ye s®Go To 4
No®Repair the Fused B+ circuit for an open. Refer to the wiring
diagrams located in the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
410
COMMUNICATION

Symptom:
*NO RESPONSE FROM PCM (PCI BUS)
POSSIBLE CAUSES
PCM PCI NO RESPONSE
PCI BUS CIRCUIT OPEN
POWERTRAIN CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
NOTE: As soon as one or more module communicates with the DRB, answer
the question.
With the DRB, enter Body then Body Computer.
With the DRB, enter Anti-Lock Brakes.
With the DRB, enter Body then Electro/Mechanical Cluster (MIC).
With the DRB, enter Passive Restraints then Airbag.
Were you able to establish communications with any of the modules?All
Ye s®Go To 2
No®Refer to symptom PCI Bus Communication Failure in the Com-
munications category.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
2 With the DRB read PCM Diagnostic Trouble Codes. This is to ensure power and
grounds to the PCM are operational.
NOTE: If the DRB will not read PCM DTC's, follow the NO RESPONSE TO
PCM (SCI only) symptom path, if vehicle will start. For NO START Condi-
tions follow symptom NO RESPONSE in Starting category.
Turn the ignition off.
Disconnect the PCM C2 harness connector.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
With the DRBIIItselect Pep Module Tools.
Select lab scope.
Select Live Data.
Select 12 volt square wave.
Press F2 for Scope.
Press F2 and use the down arrow to set voltage range to 20 volts. Press F2 again
when complete.
Connect the Black lead to the PCM ground. Connect the Red lead to the PCI Bus
circuit in the PCM connector.
Turn the ignition on.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?All
Ye s®Replace the Powertrain Control Module in accordance with the
Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
No®Repair the PCI Bus circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
412
COMMUNICATION

TEST ACTION APPLICABILITY
9 Turn the ignition off.
Disconnect the PCM C2 harness connector.
Disconnect the DRB from the DLC.
Measure the resistance of the SCI Transmit circuit between the PCM C2 connector
and the DLC.
Is the resistance below 5.0 ohms?All
Ye s®Go To 10
No®Repair the SCI Transmit circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
10 Turn the ignition off.
Disconnect the DRB from the DLC.
Disconnect the negative battery cable.
Measure the resistance between ground and both ground circuits at the DLC.
Is the resistance below 5.0 ohms for each measurement?All
Ye s®Go To 11
No®Repair the ground circuit that measured above 5.0 ohms for an
open.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
11 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 1.
415
COMMUNICATION
*NO RESPONSE FROM PCM (SCI ONLY) ÐContinued

Symptom:
*NO RESPONSE FROM RADIO
POSSIBLE CAUSES
NO RESPONSE FROM RADIO
OPEN FUSED ACCESSORY RELAY OUTPUT CIRCUIT
OPEN FUSED B+ CIRCUIT
RADIO GROUND CIRCUIT OPEN
OPEN PCI BUS CIRCUIT
RADIO
TEST ACTION APPLICABILITY
1 Turn the ignition on.
Note: As soon as one or more module communicates with the DRB, answer
the question.
With the DRB, attempt to communicate with the Airbag Control Module (ACM).
With the DRB, attempt to communicate with the Body Control Module (BCM).
Was the DRB able to I/D or establish communications with either of the modules?All
Ye s®Go To 2
No®Refer to the Communications category and perform the symptom
PCI Bus Communication Failure.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Radio C1 harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Fused Accessory Relay
Output circuit.
Is the test light illuminated?All
Ye s®Go To 3
No®Check fuse #5 in the IPM for an open. If ok, repair the Fused
Accessory Relay Output circuit for an open or short. Refer to the
wiring diagrams located in the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Disconnect the Radio C1 harness connector.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit.
Is the test light illuminated?All
Ye s®Go To 4
No®Check fuse #14 in the IPM for an open. If ok, repair the Fused B+
circuit for an open or short. Refer to the wiring diagrams located
in the Service Information.
Perform BODY VERIFICATION TEST - VER 1.
416
COMMUNICATION

TEST ACTION APPLICABILITY
4NOTE: Ensure there is PCI bus communication with other modules. If not,
refer to the PCI Bus Communication Failure symptom and repair as
necessary.
WARNING: TURN THE IGNITION OFF, DISCONNECT THE BATTERY AND
WAIT TWO MINUTES BEFORE PROCEEDING.
Disconnect the Right Side Impact Airbag Control Module harness connector.
Turn the ignition on and then reconnect the Battery.
Use Scope input cable CH7058, Cable to Probe adapter CH7062, and the red and
black test probes.
Connect the scope input cable to the channel one connector on the DRB. Attach the
red and black leads and the cable to probe adapter to the scope input cable.
Select DRB Standalone.
Select lab scope.
Select Live Data.
Select 12 volt square wave.
Press F2 for Scope, then enter to select channel.
Press F2 and use the down arrow to set voltage range to 20 volts. Press F2 again
when complete.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the Right Side Impact Airbag Control Module connector.
Observe the voltage display on the DRB Lab Scope.
Does the voltage pulse from 0 to approximately 7.5 volts?All
Ye s®Go To 5
No®Repair the PCI Bus circuit for an open.
Perform AIRBAG VERIFICATION TEST - VER 1.
5 If there are no possible causes remaining, view repair. All
Ye s®Replace the Right Side Impact Airbag Control Module (RSIACM)
in accordance with the Service Information. WARNING: Make
sure the battery is disconnected and wait 2 minutes before
proceeding.
Perform AIRBAG VERIFICATION TEST - VER 1.
419
COMMUNICATION
*NO RESPONSE FROM RIGHT SIACM ÐContinued