DTC Troubleshooting: B1205 (A and AUTO, E and AUTO)
DTC B1205, DTC indicator A and AUTO or E and AUTO:
 Heater Control Unit Lost Communication with Gauge Control Module (TACH) (VSP/NE message)
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch OFF and then ON (II).
  1. Check for DTCs.
Is DTC B1205, A and AUTO or E and AUTO indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure, check for loose wires or poor connections on the gauge control module (TACH) and heater control unit circuit.■
  1. Select UNIT INFORMATION in the BODY ELECTRICAL menu.
  1. Select CONNECTED UNIT in the UNIT INFORMATION menu.
Is gauge control module (TACH) detected?
YES -
Substitute a known-good heater control unit, and recheck. If the symptom/indication goes away, replace the original heater control unit .■
NO -
Go to Step 7 .
  1. Disconnect under-dash fuse/relay box connector Q (16P).
  1. Disconnect the gauge control module (TACH) 36P connector.
  1. 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 -
NO -
Repair open in the wire between the MICU and the gauge control module (TACH).■