| DTC B1207 or DTC indicator D and AUTO: | Climate Control Unit Lost Communication with Gauge Control Module (TACH) (ILLUMI message) |
| 1. | Clear the DTC with the HDS. |
| 2. | Turn the ignition switch OFF, and then ON (II). |
| 3. | Do the self-diagnostic with the HDS or climate control unit. |
| 4. | Check the DTCs. Is DTC B1207, or D and AUTO indicated? YES - Go to 5. NO - intermittent failure, check for loose wires or poor connections on the gauge control module (TACH) and climate control unit circuit.n |
| 5. | Select UNIT INFORMATION in the BODY ELECTRICAL menu. |
| 6. | Select CONNECTED UNIT in the UNIT INFORMATION menu. Is gauge control module detected? YES - Substitute a known-good climate control unit, and recheck. If the sympton/indication goes away, replace the original climate control unit.n NO - Go to 7. |
| 7. | Disconnect under-dash fuse/relay box connector Q (16P). |
| 8. | Disconnect the gauge control module (TACH) 36P connector. |
| 9. | Check for continuity between under-dash fuse/relay box connector Q (16P) terminal No. 6 and the gauge control module (TACH) 36P connector terminal No. 21.
Is there continuity? YES - Go to the gauge control module input test.n NO - Repair open in the wire between the MICU and the gauge control module (TACH).n |