DTC Troubleshooting: B1227 (C and AUTO)
DTC B1227 or DTC indicator C and AUTO:
 An Open in the Outside Air Temperature Sensor Circuit
  1. Clear the DTC with the HDS.
  1. Turn the ignition switch to LOCK (0) and then to ON (II).
  1. Do the self-diagnostic function with the HDS or the heater control unit.
  1. Check for DTCs.
Is DTC B1227 or C and AUTO indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure; check for loose wires or poor connections on the outside air temperature sensor circuit.■
  1. Turn the ignition switch to LOCK (0).
  1. Remove the outside air temperature sensor, and test it.
Is the outside air temperature sensor OK?
YES -
Go to Step 7 .
NO -
Replace the outside air temperature sensor .■
  1. Disconnect heater control unit connectors A (28P) and B (12P).
  1. Check for continuity between heater control unit connector A (28P) No. 24 terminal and the outside air temperature 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 outside air temperature sensor.■