Reconnect the A/C pressure switch 4P connector. Disconnect the heater control panel connector A (14P). Turn the ignition switch ON (II). Measure the voltage between the No. 4 terminal of heater control panel connector A (14P) and body ground. HEATER CONTROL PANEL CONNECTOR A (14P) Wire side of female terminals Is there battery voltage? YES - Check for loose wires or poor connections at heater control panel connector A (14P) and at the A/C pressure switch 4P connector. If the connections are good, substitute a known-good heater control panel and recheck. If the symptom/indication goes away, replace the original heater control panel. NO - Repair open in the wire between the heater control panel and the A/C pressure switch. Check for proper A/C system pressure. Is the pressure within specifications? YES - Replace the A/C pressure switch. NO - Repair the A/C pressure problem.

Except KE Model Check the No.14 (10 A) fuse in the under-dash fuse/relay box. Is the fuse OK? YES - Go to step 2. NO - Replace the fuse and recheck. Disconnect the A/C pressure switch 4P connector. Turn the ignition switch ON (II). Measure the voltage between the No. 1 terminal of the A/C pressure switch 4P connector and body ground. A/C PRESSURE SWITCH 4P CONNECTOR Wire side of female terminals Is there battery voltage? YES - Go to step 5. NO - Repair open in the wire between the A/C diode A, the ECM and the A/C pressure switch. aaa