DTC Troubleshooting: B1240 (J and A/C ON)
DTC B1240 or DTC indicator J and A/C ON:
 A Problem in the Mode Control Linkage, Doors, or Motor Circuit
  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 B1240 or J and A/C ON indicated?
YES -
Go to Step 4 .
NO -
Intermittent failure, check for loose wires or poor connections on the mode control motor circuit.■
  1. Turn the ignition switch to LOCK (0).
  1. Test the mode control motor.
Is the mode control motor OK?
YES -
Go to Step 6 .
NO -
Replace the mode control motor, or repair the mode control linkage or doors.■
  1. Disconnect the mode control motor 7P connector.
  1. Disconnect heater control unit connector A (28P).
  1. Check for continuity between the following terminals of heater control unit connector A (28P) and the mode control motor 7P connector.
    28P:
    7P:
    No. 7
    No. 2
    No. 8
    No. 1

Is there continuity?
YES -
Go to Step 9 .
NO -
Repair open in the wire(s) between the heater control unit and the mode control motor.■