BMW 316 d - malfunctioning of the electronics of the vehicle electrical system

With the above-mentioned vehicle type, it can happen that all the electronics of the vehicle electrical system fail for a short time. Communication with the engine control unit may be faulty, causing the engine to shut off.

If the above-mentioned fault applies and no definite faults have been found in the periphery of the affected systems during troubleshooting, particular attention should be paid to the transfer point of the battery positive supply in the battery box on the right-hand side of the luggage compartment.

In the course of further troubleshooting, the vehicle battery should be removed in accordance with the manufacturer's instructions. The transfer point of the battery positive supply must be checked for corrosion and thermal damage. If abnormalities can be detected here, replacing all damaged components can provide a remedy.

Furthermore, the cause of any existing corrosion on the battery positive cable must be localised. One possible cause may be water entering the battery box as a result of blocked water outlets. If the outlets on the sunroof are blocked, the water builds up and collects in the battery box at the rear on the right as well as elsewhere.

In order to test for this, water should be poured into the outlets. The water should be drained to the outside via the drain hoses. During the test, a definite water leakage underneath the vehicle to the rear and to the front has to be recognisable. If the outlets are blocked, cleaning the water drains can help. After completion of these measures, the water should drain away correctly again. If other components have been damaged by the water ingress, these are to be repaired in accordance with the manufacturer's instructions.

Once the cause of the fault has been rectified, delete the error memory and then carry out a test drive.

This fault profile may also occur in other vehicle models with comparable equipment variants.