BMW E46 Starter Not Cranking or Cranking Slowly
Why does the E46 starter not crank even though the electrics work?
The most common cause is a weak battery, and jump-starting does not help if the battery is completely flat. If the battery is fine, test the voltage at the starter's trigger terminal while turning the key. If voltage arrives but the starter does not work, the fault is in the starter motor. A clear click from the starter points to the starter or its relay.
What is checked when nothing is heard on the E46 when the key is turned?
Give the starter direct power and see whether it spins. If it does not, check the engine earth on the engine mount on the left. On an automatic, you can try moving the gear selector from park to neutral and back. The fault can also be in the relay of the EWS box, which pulls in only when the starting conditions are met.
Why does the starter crank slowly even though the battery is new?
A faulty starter can draw so much current that even a new battery is not enough. In frost, thick oils also cause slow cranking. The end bearing bush of the starter motor can wear, in which case the gear skips over and the starter spins freely.
How do you replace the M54 starter?
The starter is held by Torx bolts in a cramped location, and the bolt head rounds off easily. A socket does not fit, so a good-quality ring spanner is needed. The replacement can be done from below.