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Diagnostic Procedure

WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Did you perform the diagnostic system check? If so, go to next step. If not, see DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  2. Turn ignition off. Disconnect TCM connector C1. Check for open or shorts to ground in torque response reply signal circuit (2467) from TCM connector C1 terminal No. 9 to the PCM. Is there a short or open in the wiring harness? If so, go to next step. If not, go to step  4.
  3. Repair torque response reply signal circuit (2467). Is the repair complete? If so, go to next step.
  4. Perform the following procedure to verify the repair:
    • Clear the DTC.
    • Drive the vehicle under normal operating conditions.

    Did the DTC return? If so, go to step  1. If not, system is okay.

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