B0457

Read the instructions below then start the fault diagnostic procedure.

Symptom: Poor heating of cabin Stop the heater if it is used Heater does not start

B0457

Fault symptoms

Poor heating of cabin

Stop the heater if it is used

Heater does not start

Conditions

Resistance in the circuit for coolant temperature sensor 1 exceeds 500 kOhm for 5 seconds.

Diagnostic help

The temperature value from coolant temperature sensor 1 can be checked using the diagnostics tool.

The heater is provided with extra cabling and connector which is isolated from the ordinary cabling from the heater. This cabling and connector is not used but is connected to the control module, therefore always check that this cabling is undamaged before beginning fault tracing.

In the ordinary cabling between the heater and the 8-pin connector, there is an extra light green lead that is cut and is not used.