The starter motor, as the name suggests, produces an initial electrical surge to turn over the engine in order to start it. It requires a very high current to crank the engine, which is why it is attached to the battery with large cables.

When you turn the ignition key to the start position the battery voltage goes through a circuit to energise the starter motor. Internal parts of the starter wear over time and hence give trouble.

Starters are available from Motorparts.ie for your BMW 5 Series as new or reconditioned units. As part of the motor industry's efforts towards the environment, the old core of starters and alternators are returned whereby all internal moving and wearing parts are replaced within the old casing. In effect a reconditioned unit has proved as reliable as a new one and are much more competitively priced.