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.
- Crank engine and check engine cranking speed. If engine cranking speed is okay, go to next step. If engine cranking speed is to slow or engine will not crank, see GENERATORS & REGULATORS in appropriate STARTING & CHARGING article. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to ON position. Using scan tool, check for current or pending DTC. See RETRIEVING DIAGNOSTIC TROUBLE CODES under SELF-DIAGNOSTIC SYSTEM. If starting signal circuit DTC P0616 or P0617 is not set, go to next step. If starting signal circuit DTC P0616 or P0617 is set. See DTC P0616: STARTER RELAY CIRCUIT - LOW INPUT or DTC P0617: STARTER RELAY CIRCUIT - HIGH INPUT . After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Disconnect CMP sensor 3-pin harness connector C09, located on rear of cylinder head. See Figure . Check CMP sensor harness connector terminals for proper connection. Also check CMP sensor for proper installation. If CMP sensor connection and installation are faulty, repair as necessary and repeat DTC CONFIRMATION TEST . If CMP sensor connection and installation are okay, turn ignition switch to ON position and measure voltage between CMP sensor harness connector C09 terminals No. 1 (Blue/Black wire) and No. 3 (Purple/Red wire). See Fig 1 . If voltage is 10-14 volts, go to next step. If voltage is not 10-14 volts, repair open or short circuit in Blue/Black wire or Purple/Red wire between ECM and CMP sensor. After repair, repeat DTC CONFIRMATION TEST .
- Ensure ignition switch is in ON position. Measure voltage between CMP sensor harness connector C09 terminals No. 2 (Yellow/Blue wire) and No. 3 (Purple/Red wire). See Fig 1 . If voltage is 4-5 volts, go to next step. If voltage is not 4-5 volts, check for open or short circuit in Yellow/Blue wire between ECM and CMP sensor. If open or short circuit is found, repair as necessary and repeat DTC CONFIRMATION TEST . If open or short circuit is not found, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Remove CMP sensor. See CAMSHAFT POSITION SENSOR under ENGINE SENSORS & SWITCHES in REMOVAL & INSTALLATION article. Connect harness connector to removed CMP sensor. Disconnect ignition coil and fuel injectors harness connector. For components location, see Figure . Turn ignition switch to ON position. While rotating CMP sensor coupling, see Fig 2 , backprobe and measure voltage between ECM 30-pin harness connector C51-2 terminal No. 26 (Yellow/Blue wire) and ECM 26-pin harness connector C51-23 terminal No. 26 (Purple/Red wire). See Figure . If voltage vary from 0-6 volts, or from 6-0 volts, go to next step. If voltage does not vary from 0-6 volts, or from 6-0 volts, replace CMP sensor. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Remove signal rotor cover from CMP sensor. See Fig 3 . Check CMP sensor signal rotor for damage or contamination. If CMP sensor signal rotor is faulty, replace CMP sensor. If CMP sensor signal rotor is okay, check for intermittent problem. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES article. If intermittent problem is found, repair as necessary and DTC CONFIRMATION TEST . If no intermittent problem is found, substitute ECM with a known good unit and repeat DTC CONFIRMATION TEST .