BMW has found a rather unpleasant way for water to become a problem in some older 3, 5, and 7 Series sedans and wagons. The starter relay in these vehicles may not be adequately protected from moisture, and once water gets where it should not, corrosion can set the stage for a very problematic short circuit.
As per Germany’s Federal Motor Transport Authority, a fire hazard is the worst-case scenario. The recall covers 189,130 vehicles worldwide. Production dates for the affected vehicles range from July 29, 2014, through November 12, 2020, with 5,788 such cars falling within the campaign in BMW’s home market.
The KBA is monitoring the field safety action under reference number 16791R, with the KBA further highlighting insufficient protection against water ingress. BMW’s internal recall codes are listed by the Federal Motor Transport Authority as 0012820600 and 0012840600.
Not surprising in the least, the remedy is more substantial than checking whether the relay has survived its encounter with moisture. BMW dealers will be happy to replace the starter on affected vehicles, completely free of charge. The Munich-based manufacturer is directing customers to its recall portal, where any vehicle can be checked by its 17-character VIN.
The starter relay manages the high-amperage current transfer from the 12-volt battery to the starter motor solenoid. Inadequate sealing allows condensation, moisture, or water to penetrate the housing. Moisture contact with the internal terminals causes corrosion, and this oxidation increases electrical resistance.
Photo: BMW
Corrosion can eventually bridge the contacts, and the resulting conductive path is the perfect recipe for a short circuit. Because the starter relay is mounted alongside wiring harnesses, fluid lines, and plastic componentry, the resulting heat is a big issue. Adding insult to injury, the vehicle displays no warnings prior to a starter relay short circuit.
The KBA filing notes that no property damage or injuries are connected to this defect. BMW specifically instructed service technicians not to reseal or repair the factory starter relay. BMW revised the design of the starter relay housing to eliminate the water entry point.
BMW produced two successive generations for each of the three model lines during the July 29, 2014, through November 12, 2020, suspect timeframe. The affected chassis codes are F30/G20 for the 3 Series, F10/G30 for the 7 Series, and F01/G11for the 7 Series.
The most expensive model of the bunch is the 7er, which retails from $99,800 (excluding freight) in the United States of America for the six-cylinder 740. The 5er downsizes to a four-cylinder for its base specification, which is $60,500 from the outset for model year 2027.
Prospective customers of the 330i have to spend $48,000 at the very least, with xDrive all-wheel drive adding $2,000 to the final price. The current generations of the 3, 5, and 7 Series all feature Cluster Architecture underpinnings.