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Control Assembly: Testing and Inspection

Climate Control Power and Ground Circuits Troubleshooting

1. 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.

2. Disconnect climate control unit connector A (20P).
3. Turn the ignition switch ON (II).




4. Measure the voltage between the No.10 terminal of climate control unit connector A (20P) and body ground.

Is there battery voltage?

YES - Go to step 5.

NO - Repair open in the wire between the No.14 fuse in the under-dash fuse/relay box and the climate control unit.

5. Turn the ignition switch OFF.




6. Check for continuity between the No.20 terminal of climate control unit connector A (20P) and body ground.

Is there continuity?

YES - Check for loose wires or poor connections at climate control unit connector A (20P). If the connections are good, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit.

NO - Check for an open in the wire between the climate control unit and body ground. If the wire is OK, check for poor ground at G502.