DTC Troubleshooting: B1229 (E and AUTO)
DTC B1229 or DTC indicator E and AUTO:
 An Open in the Sunlight Sensor Circuit
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch to LOCK (0) and then to ON (II).
  1. Check for DTCs.
Is DTC B1229 or E and AUTO indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure; check for loose wires or poor connections on the sunlight sensor circuit.■
  1. Turn the ignition switch to LOCK (0).
  1. Disconnect the sunlight sensor 5P connector (with automatic lighting) or 2P connector (without automatic lighting).
  1. Disconnect heater control unit connectors A (28P) and B (12P).
  1. Check for continuity between heater control unit connector A (28P) No. 25 terminal and the sunlight sensor 2P connector No. 1 terminal.
Is there continuity?
YES -
Go to Step 9 .
NO -
Repair open in the wire between the heater control unit and the sunlight sensor.■
  1. Check for continuity between heater control unit connector B (12P) No. 10 terminal and the sunlight sensor 2P connector No. 2 terminal.
Is there continuity?
YES -
Go to Step 10 .
NO -
Repair open in the wire between the heater control unit and the sunlight sensor.■
  1. Reconnect the sunlight sensor 2P connector.
  1. Reconnect heater control unit connectors A (28P) and B (12P).
Is the sunlight sensor OK?
YES -
Check for loose wires or poor connections at heater control unit connector and at the sunlight sensor 2P connector. If the connections are good, substitute a known-good heater control unit, and recheck. If the symptom/indication goes away, replace the original heater control unit .■
NO -