DTC Troubleshooting: B1229 (E)
DTC B1229 or DTC indicator E:
 An Open in the Sunlight Sensor Circuit
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch OFF and then ON (II).
  1. Check for DTCs.
Is DTC B1229 or E 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 OFF.
  1. Disconnect the sunlight sensor 2P connector.
  1. Disconnect the heater control unit 32P connector.
  1. Check for continuity between the heater control unit 32P connector terminal No. 15 and the sunlight sensor 2P connector terminal No. 1.
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 the heater control unit 32P connector terminal No. 24 and the sunlight sensor 2P connector terminal No. 2.
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 the heater control unit 32P connector.
Is the sunlight sensor OK?
YES -
Check for loose wires or poor connections at the heater control unit 32P 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 -