Turn the ignition switch ON (II). Momentarily connect ECM/PCM connector terminals A24 and E18 with a jumper wire several times. ECM/PCM CONNECTORS A (31P) Wire side of female terminals Is there a clicking noise from the A/C compressor clutch? YES - Go to step 3. NO - Go to step 6. Start the engine. Turn the blower switch ON. Turn the A/C switch ON. Does the A/C operate? YES - The air conditioning signal is OK. NO - Substitute a known-good ECM/PCM and recheck (see page 11-313). If symptom/indication goes away, replace the original ECM/PCM.

Momentarily connect the under-hood fuse/relay box 14P connector terminal No. 10 and body ground with a jumper wire several times. UNDER-HOOD FUSE/RELAY BOX 14P CONNECTOR Wire side of female terminals Is there 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 - Check the A/C system for other symptoms.