Diagnostic Procedures
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- 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.
- Does the engine start and continue to run? If yes, go to next step. If no, go to step 4.
- Observe the Freeze Frame/Failure Records for this DTC. 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 that you observed. Does the DTC fail this ignition cycle? If yes, go to next step. If no, see DIAGNOSTIC AIDS .
- Turn ON the ignition, leaving the engine OFF. Disconnect the CKP sensor harness connector. Measure the voltage from the CKP sensor 12-volt reference circuit and a good ground with the Digital Multimeter (DMM). Does the DMM display battery voltage? If yes, go to next step. If no, go to step 7.
- Measure the voltage between the CKP sensor 12-volt reference circuit and the CKP sensor low reference circuit with the DMM. Does the DMM display battery voltage? If yes, go to next step. If no, go to step 8.
- Momentarily connect a test lamp between the signal circuit and the 12-volt reference of the CKP sensor. Does the fuel pump operate when ignition voltage is applied to the CKP sensor signal circuit? If yes, go to step 10. If no, go to step 9.
- Test for an open or a short to ground in the CKP sensor 12-volt reference circuit. If you find an open or a short to ground, repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 16. If no, go to step 14.
- Test for an open or a poor connection in the CKP sensor low reference circuit. If you find an open or poor connection, repair the condition as necessary. Did you find and correct the condition? If yes, go to step 16. If no, go to step 14.
- Test the CKP sensor signal circuit and the CKP connectors for the following conditions:
- An open.
- A short to ground or low reference.
- A short to voltage or 12-volt reference.
Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 16. If no, go to next step.
- Inspect for poor connections at the CKP sensor. If you find a poor connection repair the condition as necessary. Did you find and correct the condition? If yes, go to step 16. If no, go to next step.
- Remove the CKP sensor. Visually inspect the CKP sensor for the following conditions:
- Physical damage.
- Loose or improper installation.
- Wiring routed too closely to secondary ignition components.
Repair the circuit as necessary. Did you find and correct the condition? If yes, go to step 16. If no, go to next step.
- Inspect the CKP reluctor wheel for damage or looseness. If you find the CKP reluctor wheel damaged, replace crankshaft. See appropriate article in ENGINES. Perform the CKP system variation learn procedure. See CRANKSHAFT POSITION SENSOR under PROGRAMMING. Did you find and correct the condition? If yes, go to step 16. If no, go to next step.
- Replace the CKP sensor. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Perform the CKP System Variation Learn Procedure. See CRANKSHAFT POSITION SENSOR under PROGRAMMING. After repairs, go to step 16.
- Inspect for poor connections at the PCM. If you find a poor connection, repair the condition as necessary. Did you complete the repair? If yes, go to step 16. If no, go to 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.
- 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.
- 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.
CAUTION:
Before proceeding, remove the fuses for the ignition coil and fuel injector feed circuits in order to prevent personal injury from engine rotation, sparks, and excessive engine fueling.
NOTE:
An internally shorted CMP sensor can cause DTC P0335 to set. Test this circuit for a short before proceeding with this diagnostic test.
NOTE:
The CKP system variation learn procedure must be performed anytime the relationship between the CKP sensor and the CKP reluctor wheel is changed. See CRANKSHAFT POSITION SENSOR under PROGRAMMING.