Diagnosis & Repair Procedure
NOTE:
For better performance and results of this diagnostic procedure, usage of appropriate wiring diagram is recommended. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS
article in ELECTRICAL.
NOTE:
Perform all voltage and resistance tests using a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use an ohmmeter to isolate wiring harness shorts or opens.
- If engine system check has been performed, go to next step. If engine system check has not been performed, perform A-4: ENGINE SYSTEM CHECK under SYSTEM TESTS, then go to next step.
- Turn ignition switch to LOCK position. Disconnect ECM 30-pin harness connector C51-2, located under instrument panel, behind glove box. See Figure . Check ECM and harness connector for poor, loose, corroded or damaged connector terminals. If connector terminals are faulty, repair as necessary and repeat DTC CONFIRMATION TEST . If connector terminals are okay, measure resistance between ECM harness connector C51-2 terminals No. 19 (White/Blue wire) and No. 20 (Orange/Blue wire). See Figure . Resistance should be 484-656 ohms at 68°F (20°C). Also measure resistance between ground and ECM harness connector C51-2 terminals No. 19 (White/Blue wire) and No. 20 (Orange/Blue wire). Resistance should be one k/ohm or more. If any resistance is not as specified, go to next step. If resistances are as specified, go to step 4 .
- Disconnect CKP sensor 3-pin harness connector C57, located on rear of cylinder block, under flywheel, see Figure . Measure resistance between ground and CKP sensor connector terminals No. 2 and 3 (component side). See Fig 1 . Resistance should be 484-656 k/ohms at 68°F (20°C). If resistance is as specified, repair open or short circuit in White/Black wire or Blue wire between ECM and CKP sensor. After repair, repeat DTC CONFIRMATION TEST . If resistance is not as specified, replace CKP sensor. See CRANKSHAFT POSITION SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL & INSTALLATION article. After repair, repeat DTC CONFIRMATION TEST .
- Perform a visual inspection of CKP sensor and sensor plate, look for any damage, foreign materials attached and also correct installation. See Fig 2 . If problem is found, repair as necessary and repeat DTC CONFIRMATION TEST . If no problem is found, problem is intermittent. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. If no intermittent problem is found, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .