LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2002 >> Blazer 4D Utility, 4WD, Part Time >> Repair and Diagnosis >> External Pages >> Different car >> Section 370 (Engine Control System - Self-Diagnostics - 4.2L) >> Diagnostic Tests >> DTC P0335: Crankshaft Position Sensor "A" Circuit >> Diagnostic Procedures

Diagnostic Procedures

WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 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. Start engine. Observe the CKP active counter on scan tool. Does the CKP active counter increment? If yes, go to next step. If no, go to step  4.
  3. Observe the Freeze Frame/Failure Records for this DTC. Turn ignition off for 30 seconds. Start the engine. Operate the vehicle within the Conditions For Running the DTC. See CONDITIONS FOR RUNNING DTC . You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Does the DTC fail this ignition? If yes, go to next step. If no, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 4.2L BRAVADA, ENVOY, ENVOY XL, TRAILBLAZER & TRAILBLAZER EXT article.
  4. Turn ignition off. Disconnect the PCM connector. Measure the resistance from the CKP sensor signal circuit to the low reference circuit of the CKP sensor with a DVOM. Is the resistance 500-1000 ohms? If yes, go to next step. If no, go to step  6.
  5. Test the CKP sensor circuits for a short to voltage or a short to ground. Did you find and correct the condition? If yes, go to step  14. If no, go to step  9.
  6. Test the CKP sensor circuits for an open, short across circuit, or high resistance. Did you find and correct the condition? If yes, go to step  14. If no, go to next step.
  7. Test for an intermittent and for a poor connection at the PCM. Did you find and correct the condition? If yes, go to step  14. If no, go to next step.
  8. Test for an intermittent and for a poor connection at the CKP sensor. Did you find and correct the condition? If yes, go to step  14. If no, go to step  10.
  9. Test for shorted terminals and poor connections at the PCM. Did you find and correct the condition? If yes, go to step  14. If no, go to step  13.
  10. Remove the CKP sensor. Visually inspect the CKP sensor for foreign material passing between the CKP sensor and reluctor wheel, physical damage, excessive air gap between CKP sensor and reluctor wheel, loose or improper installation, electromagnetic interference in the CKP sensor circuits, or wiring routed too closely to secondary ignition components. Did you find and correct the conditions? If yes, go to step  14. If no, go to next step.
  11. Visually inspect the CKP reluctor wheel for physical damage, incorrect installation, or excessive end play or looseness. Did you find and correct the condition? If yes, go to step  14. If no, go to next step.
  12. Replace CKP sensor. See REMOVAL & INSTALLATION - BRAVADA, ENVOY, ENVOY XL, TRAILBLAZER & TRAILBLAZER EXT article. After repairs, go to  14.
  13. Replace PCM. See REMOVAL & INSTALLATION - BRAVADA, ENVOY, ENVOY XL, TRAILBLAZER & TRAILBLAZER EXT article. Reprogram PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  14. Clear the DTCs with scan tool. Turn ignition off for 30 seconds. Start engine. Operate vehicle within the Conditions For Running DTC. See CONDITIONS FOR RUNNING DTC . You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records. Does the DTC run and pass? If yes, go to next step. If no, go to step  2.
  15. Observe the stored information, Capture Info with scan tool. Does 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