LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2003 >> Safari Van Cargo, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 54 (Engine Control System - Self-Diagnostics - 4.2L) >> Diagnostic Tests >> DTC P0340: Camshaft Position Sensor >> Diagnostic Procedures

Diagnostic Procedures

WARNING: This page is about a different car, the 2002 Oldsmobile Bravada, 2002 GMC Envoy XL, 2002 GMC Envoy, and 2002 Chevrolet TrailBlazer. 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, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS  under SELF-DIAGNOSTIC SYSTEM.
  2. Connect the scan tool. Start and idle the engine. Use a scan tool in order to monitor the CMP active counter. Does the scan tool indicate the CMP active counter is incrementing? If yes, go to next step. If no, go to step  4 .
  3. Observe the Freeze Frame/Failure Records data. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC or as close to the Freeze Frame/Failure Records data that you observe. Does the DTC reset? If yes, go to next step. If no, see DIAGNOSTIC AIDS  .
  4. Turn OFF the ignition. Disconnect the CMP sensor connector. Turn ON the ignition, with the engine OFF. With a test lamp connected to ground, touch the 12-volt reference circuit. Does the test lamp illuminate? If yes, go to step  6 . If no, go to next step.
  5. Turn OFF the ignition. Disconnect the PCM connector C2. Test the 12-volt circuit of the CMP sensor for a short to ground, high-resistance, or an open. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  14 .
  6. Connect a test lamp to battery voltage. Touch the CMP sensor low reference circuit. Does the test lamp illuminate? If yes, go to step  8 . If no, go to next step.
  7. Turn OFF the ignition. Disconnect the PCM connector C2. Test the low reference circuit of the CMP sensor for an open. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  14 .
  8. Start the engine. Monitor the CMP active counter on the scan tool. Momentarily and repeatedly probe the CMP sensor signal circuit at the CMP harness connector with a test lamp connected to battery positive voltage. Does the CMP active counter change when performing this test? If yes, go to step  12 . If no, go to next step.
  9. Did the fuse in the jumper wire open? If yes, go to step  11 . If no, go to next step.
  10. Test the signal circuit of the CMP sensor for a short to voltage or an open. Did you find and correct the condition? If yes, go to step  16 . If no, go to step  14 .
  11. Test the signal circuit of the CMP sensor for a short to ground. Did you find and correct the condition? If yes, go to step  16 . If no, go to next step.
  12. Inspect for poor connections at the CMP sensor. Did you find and correct the condition? If yes, go to step  16 . If no, go to next step.
  13. Replace the CMP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step  16 .
  14. Inspect for poor connections at the PCM. Did you find and correct the condition? If yes, go to step  16 . If no, go to next step.
  15. Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  16. Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step  2 .
  17. Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS  . If no, system is okay.
scientia non olet · About LEMON Manuals