BUS +/- Signals Open Or No Response From Body Control Module

Possible Causes are:

ATTEMPT TO COMMUNICATE WITH ANOTHER MODULE
OPEN GROUND CIRCUIT
OPEN PCI BUS CIRCUIT
BODY CONTROL MODULE

Turn ignition on. Using the DRBIII(R), attempt to communicate with the Airbag Control Module (ACM). Using the DRBIII(R), attempt to communicate with the Controller Antilock Brake (CAB) module. Was the DRBIII(R) able to I/D or communicate with the ACM and the CAB? If yes, go to next step. If no, diagnose using appropriate procedure. See COMMUNICATION under DIAGNOSTIC TESTS. Perform BODY VERIFICATION TEST VER 1 under VERIFICATION TESTS.
Turn ignition off. Disconnect the BCM C1 harness connector. Using a 12-volt test light connected to 12 volts, probe the ground circuit (cavity No. 1). Is the test light illuminated? If yes, go to next step. If no, repair the ground circuit for an open. Perform BODY VERIFICATION TEST VER 1 under VERIFICATION TESTS.

NOTE: Ensure there is PCI Bus communication with other modules on the vehicle before proceeding. If no, diagnose using appropriate procedure. See COMMUNICATION under DIAGNOSTIC TESTS.

Disconnect the BCM C1 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 DRBIII(R). Attach the Red and Black leads and the cable to probe adapter to the scope input cable. Using the DRBIII(R), select 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. Set Probe to x10. Press F2 again, when complete. Connect the Black lead to the chassis ground. Connect the Red lead to the PCI Bus circuit in the BCM connector. Turn ignition on. Observe the voltage display on the DRBIII(R) Lab Scope. Does the voltage pulse from 0 to approximately 7.5 volts? If yes, go to next step. If no, repair the PCI Bus circuit for an open. Perform BODY VERIFICATION TEST VER 1 under VERIFICATION TESTS.
If there are no possible causes remaining, replace the Body Control Module. Perform BODY VERIFICATION TEST VER 1 under VERIFICATION TESTS.