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Test Procedure

WARNING: This page is about a different car, the 2002 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform the Battery Inspection/Test. See BATTERY TESTING & INSPECTION under ON-VEHICLE TESTING in appropriate GENERATORS & REGULATORS article in CHARGING SYSTEM in ELECTRICAL. Does the battery pass the test? If so, go to next step.
  2. Install a scan tool. Turn ON the ignition, with the engine OFF. Does the scan tool power up? If so, go to next step. If not, go to appropriate BODY CONTROL MODULES article in COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.
    NOTE: The engine may start during the following step. Turn OFF the engine as soon as you have observed the Crank power mode.
  3. Access the Ignition Switch parameter in the body control module (BCM) inputs data display list. Rotate the ignition switch through all positions while observing the ignition switch power mode parameter. Does the ignition switch parameter reading match the ignition switch position for all switch positions? If so, go to next step. If not, go to BODY CONTROL MODULES article in COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.
  4. Turn ON the ignition, with the engine OFF. Attempt to communicate with each of the following modules on the class 2 serial data circuit:
    • Amplifier (AMP).
    • Body Control Module (BCM).
    • Instrument Panel Cluster (IPC).
    • Memory Mirror Module (MMM).
    • Memory Seat Module (MSM).
    • Onstar (ONS).
    • Radio (IRC).
    • Powertrain Control Module (PCM).
    Does the scan tool communicate with all modules on the class 2 serial data circuit? If so, go to next step. If not, go to BODY CONTROL MODULES article in COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT.
  5. Select the Display DTCs function for each module. If using a Tech 2, use the Class 2 DTC Check feature in order to determine which modules have DTCs set. Record all of the displayed DTCs, the DTC status, and the module which set the DTC. Does the scan tool display any DTCs? If so, go to next step. If not, go to ENGINE ELECTRICAL SYMPTOMS  under TROUBLE SHOOTING.
  6. Does the scan tool display any DTCs which begin with a "U"? If so, go to BODY CONTROL MODULES article in COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If not, go to next step.
  7. Does the scan tool display DTC B1000, B1007 or B1009? If so, go to BODY CONTROL MODULES article in COMMUNICATION DEVICES in ACCESSORIES & EQUIPMENT. If not, DIAGNOSTIC TROUBLE CODE DEFINITIONS  .
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