Overheating
â–¶ How to fix
Check the fuel supply.Check that the pipes for air supply or air venting are not blocked.Check the flame monitor.Check the overheating sensor.Instructions for the checking procedures are found in the work description in Multi under 18-90 "H13, ATA Auxiliary heater - Air".
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
The difference in temperature between the temperature sensor and overheat sensor is too great.
Possible cause
Blocked air supply to the auxiliary heater, cold air.Blocked air vent from the auxiliary heater, heated air.Faulty flame monitor or control unit.Check the fuel supply.