Insufficient voltage
â–¶ How to fix
Check the voltage supply. Measurement points 1 and 9 in connector from auxiliary heater to vehicle cable harness. The measurement should not be different from the voltage value from the battery. If the voltage is above 20 V, renew the control unit. If the voltage is below 20 V, check the voltage supply. Check connectors and wiring. Check the positive and negative connections. 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 low. Below 20 V.
Possible cause
Fault in the cable harness, battery or control unit.