Operation CHARM: Car repair manuals for everyone.

Control Assembly: Testing and Inspection




Climate Control Unit Troubleshooting

1. Check the No. 30 (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. If the fuse blows again, check for a short in the No. 30 (10 A) fuse circuit.�

2. Turn the ignition switch to ON (II).

3. Measure the voltage between climate control unit connector A (40P) terminal No. 3 and body ground.





Is there battery voltage?

YES -

Go to step 4.

NO -

Repair an open in the wire between the No. 30 (10 A) fuse in the under-dash fuse/relay box and the climate control unit.�

4. Turn the ignition switch to LOCK (0).

5. Check for continuity between climate control unit connector A (40P) terminal No. 37 and body ground.





Is there continuity?

YES -

Go to step 6.

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 G506.�

6. Disconnect climate control unit connector A (40P).

7. Disconnect under-dash fuse/relay box connector N (45P).

8. Check for continuity between under-dash fuse/relay box connector N (45P) terminal No. 28 and climate control unit connector A (40P) terminal No. 4.





Is there continuity?

YES -

Check for loose wires and poor connections at climate control unit connector A (40P). 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 Climate Control Unit Removal/Installation.�

NO -

Repair an open in the wire between the MICU and the climate control unit.�