A/C Signal Circuit Troubleshooting

1. Start the engine.

1. Turn the blower switch ON.

1. Turn the A/C switch ON.

1. Check the A/C CLUTCH in the DATA LIST with the HDS.

Is it ON?

YES | - | Go to Step 5 .
NO | - | Go to the A/C pressure switch circuit test.

1. Check the A/C system.

Does the A/C system operate?

YES | - | The air conditioning signal is OK.■
NO | - | Go to Step 6 .

1. Turn the ignition switch OFF.

1. Turn the ignition switch ON (II).

1. Activate the A/C CLUTCH in the INSPECTION MENU with the HDS.

Is there a clicking noise from the A/C compressor clutch?

YES | - | Go to the A/C system for the other symptoms.■
NO | - | Go to Step 9 .

1. Momentarily connect under-hood fuse/relay box 16P connector terminal No. 15 to body ground with a jumper wire several times.

Is there a clicking noise from the A/C compressor clutch?

YES | - | Repair open in the wire between the ECM/PCM (E18) and the A/C clutch relay.■
NO | - | Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM / PCM .■