Overvoltage
â–¶ How to fix
Check the voltage supply. Measurement points 1 and 9 in the connector from the auxiliary heater toward the vehicle cable harness. If the voltage is above 30 V, check the alternator. If the voltage is below 30 V, renew the control unit. Check connectors and wiring. Delete the fault code and test run the auxiliary heater and vehicle.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
The voltage was too high.
Possible cause
Fault in alternator or control unit.