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Diagnostic Procedures

WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue and 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
  1. Did you perform the Diagnostic System Check - Engine Controls? If yes, go to next step. If no, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
    NOTE: If engine is making a knock noise, repair engine mechanical condition before continuing with this test.
  2. Using scan tool, observe and record the FREEZE FRAME/FAILURE RECORDS data for this DTC. Turn ignition off for 30 seconds. Start engine. Operate vehicle within conditions for running the DTC or as close to recorded FREEZE FRAME/FAILURE RECORDS data as possible. See CONDITIONS FOR RUNNING DTC . If DTC resets, go to next step. If DTC does not reset, fault may be intermittent. See INTERMITTENT CONDITIONS  under SELF-DIAGNOSTIC SYSTEM.
  3. Turn ignition off. Disconnect PCM harness connector. Set DVOM to 400 millivolts AC hertz scale. Observe frequency between the signal circuit and a good ground. While observing DVOM, use a non-metallic object and tap on side of engine block near knock sensor. Knock sensor is located near engine oil pressure sensor. If frequency fluctuates while tapping block, go to step  7. If frequency does not fluctuate, go to next step.
  4. Check the KS signal circuit between the PCM and knock sensor connector for open, short to ground, or short to voltage. If any problems are found, repair wiring as necessary. After repairs, go to step  9. If no problems are found, go to next step.
  5. Check knock sensor connector for poor connection. Repair connector as necessary. After repairs, go to step  9. If connector is okay, go to next step.
  6. Replace knock sensor. After repairs, go to step  9.
  7. Check for poor connections at PCM. Repair connector as necessary. After repairs, go to step  9. If connector is okay, go to next step.
  8. Replace PCM. Program replacement PCM. See PROGRAMMING . After repairs, go to next step.
  9. Turn ignition off. Reconnect all disconnected connectors. Turn ignition on. Using scan tool, clear DTCs. Turn ignition off for 30 seconds. Start engine. Operate vehicle within conditions for running the DTC. See CONDITIONS FOR RUNNING DTC . If DTC runs and passes, go to next step. If DTC resets, go to step  2.
  10. Using scan tool, check for any other DTCs that are set. If no other DTCs are set, system is okay. If any other DTCs are set, repair DTCs as necessary. See DIAGNOSTIC TROUBLE CODE DEFINITIONS .
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