Module Communications Network

1. Verify the customer concern.
2. Visually inspect the following for obvious signs of electrical damage:

VISUAL INSPECTION CHART

Electrical
^ Fuses
^ Damaged wiring harness
^ Loose or corroded connectors
^ 4-wheel anti-lock brake control module
^ Electronic Crash Sensor (ECS) module
^ Powertrain Control Module (PCM)
^ Natural Gas Vehicle Module (NGVM)
^ Auxiliary Powertrain Control Module (APCM)

3. If the concern remains after the inspection, connect the 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 properly 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 H. Test H: No Module/Network Communication

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