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Diagnostic Procedure

WARNING: This page is about a different car, the 2003 Pontiac Grand Prix, 2003 Chevrolet Malibu, and 2003 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform diagnostic system check - engine controls. See DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check - engine controls, go to next step.
  2. Is DTC P0560 set? If yes, diagnose engine electrical system. Go to appropriate GENERATORS & REGULATORS article in ELECTRICAL. If no, go to next step.
  3. Using a scan tool, select the OUTPUT DRIVER DATA list. Observe the parameters on the scan tool. Do any parameters indicate a fault present? If yes, go to next step. If no, go to step  5.
  4. Test for a short to voltage on the control circuit of the component that indicated a fault. Did you find and correct the condition? If yes, go to step  6. If no, go to next step.
  5. Replace PCM. See POWERTRAIN CONTROL MODULE in appropriate REMOVAL & INSTALLATION article. Perform PCM relearn procedure. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After replacing PCM, go to next step.
  6. Using scan tool, clear DTCs. Turn ignition switch to OFF position for 30 seconds. Start the engine. Operate vehicle within Conditions For Running Test. See CONDITIONS FOR RUNNING TEST . Did the DTC fail this ignition? If yes, go to step  2. If no, go to next step.
  7. Using the scan tool, observe the stored information in CAPTURE INFO. Does scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay at this time.
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