Common issues & diagnosis
Starter motors are not a particularly common problem in later BMWs—but occasionally they can fail or wear out.
Usually the issue is electrical—connectors can overheat and burn out, both the relay and solenoid can fail. Sometimes the teeth on the gear can also wear out.
If there are no obvious clues to why the starter motor isn’t engaging it’s worth checking the battery first.
What is the part's function?
Starter motors assist with starting the vehicle’s engine. When the ignition is activated, power is sent from the battery to the starter motor—which drives the gear whilst simultaneously activating the solenoid, which aligns the gear with the flywheel. In turn the flywheel is then driven, which cranks the engine.
How to determine fitment compatibility
Within each model generation, most engines from the same family will share the same starter motor—and starter motors can also be interchangeable between engine families.
In saying that, there are often a few types of starter motor for any given model generation—and engine families can have different types within them too.
The best way to determine if a starter motor is compatible with your vehicle is by matching the BMW part numbers from the catalogue. You can also do this by getting the BMW or manufacturer’s part numbers (Bosch, etc.) physically off you unit—but this will probably be a superseded part number.
Provide our team with your vehicle’s 17-digit VIN—and we can check our stock for a compatible part.
Interchangeability between models
Starter motors are often interchangeable between similar/alike engines.