Module Communications Network

1. Verify the customer concern by operating the system in question.
2. Visually inspect for obvious signs of electrical damage.

VISUAL INSPECTION CHART

Electrical
^ Battery Junction Box (BJB) Fuse 12 (30A)
^ Wiring harness
^ Loose or corroded connections
^ Anti-lock brake control module
^ Electronic Automatic Temperature Control (EATC) module
^ Natural Gas Vehicle Module (NGVM)
^ Restraint Control Module (RCM)
^ Driver Door Module (DDM)
^ Lighting Control Module (LCM)
^ Powertrain Control Module (PCM)
^ Variable Assist Power Steering (VAPS) module
^ Rear Air Suspension Module (RASM)

3. If the concern remains after the inspection, connect diagnostic tool to the Data Link Connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool does not communicate with the vehicle:
^ check that the program card is correctly installed.
^ check the connections to the vehicle.
^ check the ignition switch position.

If the diagnostic tool still does not communicate with the vehicle, GO to Pinpoint Test M. Test M

4. GO to Pinpoint Test PC. Pinpoint Test PC (Precheck)