| 1. | Check the No. 30 (7.5A) fuse in the under-dash fuse/relay box. Is the fuse OK? YES - Go to 2. NO - Replace the fuse, and recheck.n |
| 2. | Disconnect climate control unit connector B (16P). |
| 3. | Turn the ignition switch ON (II). |
| 4. | Measure the voltage between the No. 4 terminal of climate control unit connector B (16P) and body ground. Is there battery voltage? YES - Go to 5. NO - Repair open in the wire between the No. 30 fuse in the driver¢s under-dash fuse/relay box and the climate control unit.n |
| 5. | Turn the ignition switch OFF. |
| 6. | Check for continuity between the No. 6 terminal of climate control unit connector B (16P) and body ground. Is there continuity? YES - Go to 7. 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 G503.n |
| 7. | Perform the A/C communication in the Self-Diagnostic Function to obtain the IS-BUS communication varification status Is the communication OK? YES - Check for loose wires or poor connections at climate control unit connector B (16P). If the connections are good, substitute a known-good climate control unit and printed circuit board, and recheck. If the symptom/indication goes away, replace the original climate control unit and printed circuit board.n NO - Check for loose wires or poor connections at climate control unit connector B (16P). 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.n |