( TL19E00K733000Y1225FAAT00 )

DTC Troubleshooting: B1225 (A and AUTO)

1. Check for continuity between heater control unit connector B (12P) No. 10 terminal and the in-car temperature sensor 2P connector No. 2 terminal.

Is there continuity?

YES | - | Check for loose wires or poor connections at heater control unit connectors A (28P), B (12P), and at the in-car temperature 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 | - | Repair open in the wire between the heater control unit and the in-car temperature sensor.■