Diagnostic Procedures
WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
- 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.
- Install a scan tool. Attempt to start the engine. With a scan tool, monitor the DTC information. Are all three DTCs P0335, P0340, and P0385 set? If yes, go to step 11. If no, go to next step.
- Start the engine. With a scan tool, monitor the CKP sensor status parameter. Does the scan tool indicate the CKP sensor status as ANGLE? If yes, go to next step. If no, go to step 5.
- With the engine running, move the harnesses and connectors related to CKP "A" sensor (by hand only). If the CKP sensor status changes or an engine stall occurs, locate and repair the condition in the harnesses/connectors related to CKP "A" sensor. Did you find and correct the condition? If yes, go to step 21. If no, see DIAGNOSTIC AIDS .
- Turn the ignition ON, with the engine OFF. Disconnect the CKP "A" sensor. Connect the test lamp between the 12-volt reference circuit of the CKP "A" sensor and a good ground. Does the test lamp illuminate? If yes, go to next step. If no, go to step 8.
- Connect the test lamp between the 12-volt reference circuit of the CKP "A" sensor and the low reference circuit of the CKP "A" sensor. Does the test lamp illuminate? If yes, go to next step. If no, go to step 9.
- Turn the ignition ON, with the engine OFF. With a scan tool, clear the DTCs. With a scan tool, command the PCM to operate in time mode "A". With the test lamp connected to battery voltage, repeatedly touch the CKP "A" sensor 2 signal circuit in the harness connector. With a scan tool, observe the 24X crank sensor data parameter. Does the scan tool indicate an RPM while touching the test lamp to the signal circuit? If yes, go to step 15. If no, go to step 10.
- Turn the ignition OFF. Disconnect the PCM harness connector. Test the 12-volt reference circuit of the CKP "A" sensor for an open. Did you find and correct the condition? If yes, go to step 21. If no, go to step 16.
- Turn the ignition OFF. Disconnect the PCM harness connector. Test the low reference circuit of the CKP "A" sensor for an open. Did you find and correct the condition? If yes, go to step 21. If no, go to step 16.
- Turn OFF the ignition. Disconnect the PCM harness connector. Turn the ignition ON, with the engine OFF. Test the CKP "A" signal circuit for an open, a short to ground or either CKP low reference, a short to voltage, or a short to the CKP "B" signal circuit. Did you find and correct the condition? If yes, go to step 21. If no, go to step 16.
- Disconnect the CMP sensor harness connector. With a scan tool, monitor the 12-Volt Reference parameter. Does the scan tool display OK? If yes, go to step 17. If no, go to next step.
- Raise the vehicle. Disconnect CKP "A" sensor harness connector. With a scan tool, monitor the 12-Volt Reference parameter. Does the scan tool display OK? If yes, go to step 18. If no, go to next step.
- Disconnect the CKP "B" sensor harness connector. With a scan tool, monitor the 12 Volt Reference parameter. Does the scan tool display OK? If yes, go to step 19. If no, go to next step.
- Turn OFF the ignition. Disconnect the PCM harness connectors. Test the 12-volt reference circuit of the CKP "A", the CKP "B", and the CMP sensor for a grounded circuit. Did you find and correct the condition? If yes, go to step 21. If no, go to step 20.
- Inspect for poor connections at the harness connector of the CKP "A" sensor. Did you find and correct the condition? If yes, go to step 21. If no, go to step 18.
- Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If yes, go to step 21. If no, go to step 20.
- Replace the CMP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 21.
- Replace the CKP "A" sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 21.
- Replace the CKP "B" sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. After repairs, go to step 21.
- Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See POWERTRAIN CONTROL MODULE under PROGRAMMING. After repairs, go to next step.
- Use the scan tool in order to clear the DTCs. 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.
- With a scan tool, observe the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.
NOTE:
If DTC P0386 is also set, continue with the diagnostic procedure for DTC P0335 before diagnosing DTC P0386.