A/C Signal Circuit Troubleshooting

WARNING: This page is about a different car, the 2008 Acura TSX, 2007 Acura TSX, 2006 Acura TSX, 2005 Acura TSX, and 2004 Acura TSX. However, it is still accessible from the selected car via links, so may be relevant.

Start the engine.
Turn the blower switch on.
Turn the A/C switch on.
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 troubleshooting (see A/C PRESSURE SWITCH AND THERMAL PROTECTER CIRCUIT TROUBLESHOOTING ).
Check the A/C system.
Does the A/C system operate?

YES -The air conditioning system circuit is OK.

NO -Go to step 6.
Turn the ignition switch OFF.
Turn the ignition switch ON (II).
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 (see A/C SYSTEM TEST ).

NO -Go to step 9.
Momentarily connect under-hood fuse/relay box 16P connector terminal No. 15 to body ground with a jumper wire several times.

Fig 1: Connecting Under-Hood Fuse/Relay Box 16P Connector Terminal No. 15 To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.

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 (see UPDATING THE ECM/PCM ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM; '04-05 models (see '04-05 MODELS ), '06-08 models (see '06-08 MODELS ).