( TL19E20A20336112101FAAT00 )

A/C Signal Circuit Troubleshooting

1. Start the engine, and let it idle.

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.

Does it indicate ON?

YES | - | Go to Step 5 .
NO | - | Do the A/C system test. ■

1. Check the A/C system.

Does the A/C system operate?

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

1. Turn the ignition switch to LOCK (0).

1. Turn the ignition switch to 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 | - | Do the A/C system test. ■
NO | - | Go to Step 9 .

1. Turn the ignition switch to LOCK (0).

1. Jump the SCS line with the HDS.

1. Disconnect ECM/PCM connector A (44P).

1. Turn the ignition switch to ON (II).

1. Momentarily connect ECM/PCM connector terminal A14 to body ground with a jumper wire several times.

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

YES | - | 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. ■
NO | - | Check for poor connections or loose terminals at the A/C clutch relay and the ECM/PCM. If the connections are OK, check the A/C compressor clutch relay, repair open in the wire between the ECM/PCM (A14) and the A/C compressor clutch relay and the other A/C systems.■