1. Start the engine, and let it idle.
2. Turn the blower switch on.
3. Turn the A/C switch on.
4. Check the A/C CLUTCH in the DATA LIST with the HDS.
Does it indicate ON? YES-Go to step 5.
5. Check the A/C system.
Does the A/C system operate? YES-The air conditioning system circuit is OK.
NO-Go to step 6.
6. Turn the ignition switch OFF.
7. Turn the ignition switch ON (II).
8. Activate the A/C CLUTCH in the INSPECTION MENU with the HDS.
Is there a clicking noise from the Ale compressor clutch? YES-Do the A/C system test.
NO-Go to step 9.
9. Turn the ignition switch OFF.
10. Jump the SCS line with the HDS.
11. Disconnect PCM connector A (44P).
12. Turn the ignition switch ON (II).
13. Momentarily connect PCM connector terminal A14 to body ground with a jumper wire several times.
Is there a clicking noise from the Ale compressor clutch? YES-Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
NO-Check for poor connections or loose terminals at the A/C compressor clutch relay and the PCM. If the connections are OK, check the A/C compressor clutch relay. Then repair open in the wire between the PCM (A 14) and the A/C compressor clutch relay and the other A/C systems.
Alternator FR Signal Circuit Troubleshooting
1. Start the engine, and let it idle.
2. Monitor the ALTERNATOR in the DATA LIST with the HDS.
3. Check if the indicated percentage varies when the headlight switch is turned on.
Does the percentage vary? YES-The alternator signal circuit is OK.
NO-Go to step 4.
4. Turn the headlight switch and ignition switch OFF.
5. Jump the SCS line with the HDS.
6. Disconnect the alternator 4P connector.
7. Disconnect PCM connector B (44P).
8. Check for continuity between body ground and PCM connector terminal B43.
Is there continuity? YES-Repair short in the wire between the PCM (B43) and the alternator.
NO-Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.