Tech Tips

Use this comprehensive information library whenever you need helpful hints from car repair professionals. Whether you are a professional or a DIY mechanic, you’re sure to find the tips you need to insure a job well done. Click here to go back to the previous page any time during your search.

BMW

Late Model BMWs Starter Failures

The starter on many late model BMWs incorporates a one-way clutch which allows the engine to spin faster than the starter during engagement.  While this makes for smooth, quiet starting and gear engagement, it also provides opportunity for problems!  It seems that many Beamers requiring a Bosch remanufactured starter SR0445X are experiencing multiple starter failures due to the starter motor remaining engaged after the engine has started and the ignition key has been released.  

You guessed it....there's nothing wrong with the starter, it's the ignition lock cylinder assembly!  The mechanical portion of the ignition switch gets hung up in the start position and doesn't return to the run position.  When this happens, the one-way clutch in the starter allows the starter to continue spinning with the engine; prolonged use in this condition will overheat the starter causing permanent damage as well as draining the battery.  To correct this condition, the entire lock cylinder, steering lock, and electrical switch unit must be replaced.   

Go back