12 63 520 Replacing DME master relay

Necessary preliminary tasks: 

• Switch off ignition
• Open electronics box.

Remove DME master relay.

Fig 1: Locating DME Master Relay

Courtesy of BMW OF NORTH AMERICA, INC.

Notes on troubleshooting:

If the starter motor cranks the engine during the starting sequence but the engine fails to fire, then:

1. Check engine fuses
2. If the fuses have blown, replace them completely with the fuse holder
3. Find out why fuses have blown

Continue troubleshooting as per DIS (BMW diagnostic equipment) instructions.