Air Conditioning Signal: 3.2TL
- Turn ignition off. Disconnect A/C pressure switch connector. Turn ignition on. Measure voltage by backprobing between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and PCM 25-pin connector "B" terminal No. 20 (Brown/Yellow wire). If around 5 volts are present, go to next step. If around 5 volts are not present, go to step 3.
- Turn ignition off. Reconnect A/C pressure switch connector. Turn ignition on. Momentarily connect jumper wire several times between PCM 32-pin connector "A" terminal No. 17 (Red wire) and PCM 25-pin connector "B" terminal No. 20 (Brown/Yellow wire). If A/C compressor clutch does not make a clicking noise, go to step 4. If A/C compressor clutch makes a clicking noise, start engine. Turn blower switch and A/C on. If A/C operates, A/C signal is okay. If A/C does not operate, go to step 5.
- Turn ignition off. Disconnect PCM 32-pin connector "A". Measure continuity between ground and PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire). If continuity is present, repair short circuit in Blue/Red wire between PCM 32-pin connector "A" terminal No. 27 and A/C pressure switch. If continuity is not present, substitute known-good PCM from donor vehicle. Cut temporary key from a non-immobilizer key blank and tape donor vehicle key to it backwards in order to deactivate immobilizer system during testing. If voltage measured between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and PCM 25-pin connector "B" terminal No. 20 (Brown/Yellow wire) is now around 5 volts, replace original PCM. If measured voltage is not around 5 volts, recheck A/C system. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
- Momentarily connect jumper wire several times between underhood fuse/relay block 16-pin connector "D" terminal No. 11 (Red wire) and ground. If A/C compressor clutch makes a clicking noise, repair open circuit in Red wire between PCM 32-pin connector "A" terminal No. 17 and A/C clutch relay. If A/C compressor does not make a clicking noise, problem is with A/C system. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
- Measure voltage between PCM 32-pin connector "A" terminal No. 27 (Blue/Red wire) and PCM 25-pin connector "B" terminal No. 20 (Brown/Yellow wire). If less than one volt is present, replace PCM. If one volt or more is present, repair open circuit in Blue/Red wire between PCM 32-pin connector "A" terminal No. 27 and A/C pressure switch.