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 TEST D: ENGINE SYSTEM CHECK under SYSTEM TESTS, then go to next step.
- Turn ignition switch to LOCK position. Disconnect A/C condenser fan control relay from engine compartment fuse/relay box. See Figure. Turn ignition switch to ON position. Measure voltage between ground and A/C condenser fan control relay connector C09 terminals No. 2 (Light/Green wire). See Fig 1. If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to step 4.
- Turn ignition switch to LOCK position. Disconnect A/C compressor control relay from engine compartment fuse/relay box. See Figure. Turn ignition switch to ON position. Measure voltage between ground and A/C condenser fan control relay connector E09 terminals No. 2 (Light/Green wire). See Figure. If voltage is 10-14 volts, replace A/C compressor control relay. After repair, repeat DTC CONFIRMATION TEST . If voltage is not 10-14 volts, repair open or short circuit in Light/Green wire between fuse box, A/C condenser fan control relay and A/C compressor control relay. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Reconnect A/C condenser fan control relay to fuse/relay box. Disconnect ECM harness connector G04. See Figure. Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector G04 terminal No. 32 (Blue/Yellow wire). See Figure. If voltage is not 10-14 volts, go to next step. If voltage is 10-14 volts, go to step 8.
- Turn ignition switch to LOCK position. Disconnect A/C condenser control relay from fuse/relay box. Measure resistance between ground and ECM harness connector G04 terminal No. 32 (Blue/Yellow wire). See Figure. If resistance is infinity, go to next step. If any resistance is found, repair short to ground in Blue/Yellow wire between ECM and A/C condenser control relay. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to ON position. Measure voltage between ground and ECM harness connector G04 terminal No. 32 (Blue/Yellow wire). See Figure. If voltage is zero volts, go to next step. If any voltage is found, repair short to voltage in Blue/Yellow wire between ECM and A/C condenser control relay. After repair, repeat DTC CONFIRMATION TEST .
- Turn ignition switch to LOCK position. Perform A/C condenser fan control relay component test as follows:
- Check continuity between A/C condenser fan control relay terminals "c" and "d". See Fig 2. If continuity is not found, go to next step. If continuity is found, replace A/C condenser fan control relay and repeat DTC CONFIRMATION TEST .
- Connect fused jumper wire between battery (+) and radiator fan control relay terminal "a", also connect another jumper wire between battery (-) and radiator fan control relay terminal "b". See Fig 2. Check continuity between A/C condenser fan control relay terminals "a" and "b". See Fig 2. If continuity is not found, replace A/C condenser fan control relay and repeat DTC CONFIRMATION TEST . If continuity is not found, repair open circuit in Blue/Yellow wire between ECM and A/C condenser fan control relay. After repair, repeat DTC CONFIRMATION TEST .
- Reconnect G04 harness connector to ECM and A/C condenser fan control relay to fuse/relay box. Start engine and allow it to idle until reaches 207°F (97°C). Backprobe and measure voltage between ground and ECM harness connector G04 terminals No. 32 (Blue/Yellow wire). See Figure. If voltage is 1.5 volts or more, replace ECM. See ENGINE CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL & INSTALLATION article. After repair, repeat DTC CONFIRMATION TEST . If voltage is less than 1.5 volts, 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 .