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TEST ACTION APPLICABILITY
14 Select the diagnostic repair. All
For this condition:
Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
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IGNITION RUN OUTPUT SHORT ÐContinued
Page 386 of 4284
Symptom:
INTERNAL BCM FAILURE
When Monitored and Set Condition:
INTERNAL BCM FAILURE
When Monitored: The BCM detects an internal fault for 10 seconds.
Set Condition: The DTC will set if the BCM detects an internal fault.
POSSIBLE CAUSES
INTERNAL BCM FAILURE
TEST ACTION APPLICABILITY
1 Connect the DRB to the Data Link Connector.
Turn the ignition on.
With the DRB, erase BCM DTC's.
Turn the ignition off then turn the ignition on.
With the DRB, read BCM DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
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COMMUNICATION
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Symptom:
LEFT PSD MESSAGES NOT RECEIVED
When Monitored and Set Condition:
LEFT PSD MESSAGES NOT RECEIVED
When Monitored: When the Body Control Module is awake.
Set Condition: The BCM does not sense a response from the Left Power Sliding Door
Module.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE LEFT SLIDING DOOR CONTROL MODULE
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, attempt to communicate with the Left Sliding Door Control Module.
Was the DRB able to I/D or communicate with the Left Sliding Door Control Module?All
Ye s®Go To 2
No®Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRB, erase DTC's.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRB, read DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
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COMMUNICATION
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Symptom:
LIFTGATE MODULE MESSAGES NOT RECEIVED
When Monitored and Set Condition:
LIFTGATE MODULE MESSAGES NOT RECEIVED
When Monitored: When the Body Control Module is awake.
Set Condition: The BCM does not sense a response from the Power Liftgate Control
Module.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE POWER LIFTGATE MODULE
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, attempt to communicate with the Power Liftgate Module.
Was the DRB able to I/D or communicate with the Power Liftgate Module?All
Ye s®Go To 2
No®Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRB, erase DTC's.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRB, read DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
359
COMMUNICATION
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Symptom:
MIC MESSAGES NOT RECEIVED
When Monitored and Set Condition:
MIC MESSAGES NOT RECEIVED
When Monitored: With the ignition in run, and the IOD fuse installed.
Set Condition: The BCM does not receive any messages from the Instrument Cluster
(MIC) for at least 5 seconds.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE MIC
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, attempt to communicate with the Instrument Cluster (MIC).
Was the DRB able to I/D or communicate with the Instrument Cluster (MIC)?All
Ye s®Go To 2
No®Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRB, erase DTC's.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRB, read DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
360
COMMUNICATION
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Symptom:
MSM MESSAGES NOT RECEIVED
When Monitored and Set Condition:
MSM MESSAGES NOT RECEIVED
When Monitored: With the ignition in run, and the IOD fuse installed.
Set Condition: The BCM does not receive any messages from the Memory Seat Module
(MSM) for at least 0.125 seconds.
POSSIBLE CAUSES
ATTEMPT TO COMMUNICATE WITH THE MEMORY SEAT MODULE
BODY CONTROL MODULE
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, enter Body then Memory Seat Module.
Was the DRB able to I/D or communicate with the MSM?All
Ye s®Go To 2
No®Refer to the Communication category for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.
2 With the DRB, erase DTC's.
Cycle the ignition switch from off to on and wait approximately 1 minute.
With the DRB, read DTC's.
Did this DTC reset?All
Ye s®Replace the Body Control Module.
Perform BODY VERIFICATION TEST - VER 1.
No®Test Complete.
361
COMMUNICATION
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Symptom:
NO PCI MESSAGES FROM CD CHANGER
When Monitored and Set Condition:
NO PCI MESSAGES FROM CD CHANGER
When Monitored: With the ignition on and the radio on.
Set Condition:
POSSIBLE CAUSES
CD CHANGER (DIN) CABLE
CD CHANGER PCI BUS CIRCUIT OPEN
IGNITION SWITCH OUTPUT CIRCUIT OPEN
RADIO GROUND CKT OPEN
CD CHANGER
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Radio C4 connector (DIN cable) from the Radio and the CD Changer.
Visually inspect the Radio C4 (DIN) cable for damage.
In the next step check for open wires in the DIN cable.
Measure the resistance of the each DIN cable circuit between the Radio DIN cable
connector and the CD Changer DIN cable connector.
In the next step check for wires shorted to the DIN cable metal connectors.
Measure the resistance between each Radio C4 connector ( DIN cable) circuit and the
Radio Din cable metal connector.
Is the DIN cable circuits shorted together or open?All
Ye s®Replace the CD Changer (DIN) cable.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 2
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Page 392 of 4284

TEST ACTION APPLICABILITY
2 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.
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.
Disconnect the CD Changer harness connector (DIN cable).
Reconnect the Radio C4 (DIN Cable) harness connector.
Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus
circuit in the CD Changer DIN Cable connector.
Turn the ignition on.
Turn the Radio and CD Changer on.
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 3
No®Replace the Radio.
Perform BODY VERIFICATION TEST - VER 1.
3 Turn the ignition off.
Disconnect the CD Changer harness connector (DIN cable).
Turn the ignition on.
Turn the Radio and the CD Changer on.
Using a 12-volt test light connected to ground, probe the Ignition Switch Output
circuit in the CD Changer DIN Cable connector.
Is the test light illuminated?All
Ye s®Go To 4
No®Replace the Radio.
Perform BODY VERIFICATION TEST - VER 1.
4 Turn the ignition off.
Disconnect the CD Changer harness connector (DIN cable).
Using a 12-volt test light connected to 12-volts, probe the CD Changer ground circuit
in the CD Changer connector (DIN cable).
Is the test light illuminated?All
Ye s®Go To 5
No®Replace the Radio.
Perform BODY VERIFICATION TEST - VER 1.
5 If there are no possible causes remaining, view repair. All
Repair
Replace the CD Changer.
Perform BODY VERIFICATION TEST - VER 1.
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COMMUNICATION
NO PCI MESSAGES FROM CD CHANGER ÐContinued