Radiator Fans Control Unit Faulty / Power Supply / Overtemperature

P048000

Diagnosis information DME control unit

Radiator fans Control unit faulty / Power supply / Overtemperature

DANGER
High voltage.
Death or severe injuries due to high voltage or high current.

- De-energise the vehicle in accordance with the guidelines.
- Work must not be performed on parts carrying a high voltage.

Diagnostic conditions
The control unit must be active in order to test internal function sequences and diagnosable inputs/outputs.
In the event of a fault, check whether the fault is permanently >present<. To perform the check, erase the fault memory, meet the diagnostic conditions and read out the fault memory again.
- Ignition on
- Actuation of radiator fan via drive link test (6 min) with a pulse duty factor of 10%

Possible fault causes
- Control unit faulty
- Power supply
- Overtemperature

NOTE:
Diagnosis/Fault finding.
- Perform a drive-link test
- Check fuse, terminal 30.
- Short circuit to B+/ground/between lines or open circuit in the lines