Mechanics

BMW 540I FUSE PROBLEM

1994 BMW 540i • 67,000 miles

No start. No power to fuse 23(fuel pump). Have power at fuel pump relay. Replaced dme. No help.


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Dcraig10004
March 17, 2013.



Dme? Please explain

there should be 2 feeds to the relay. One is key on power and the other is 12 volts constant.

If there is no power to the fuse box fuse, then you may have a wiring issue at the fuse box or check fusible links

Roy

ASEMaster6371
Mar 17, 2013.
The DME(bmw lingo) is the ECM. It was a bad CPS. During troubleshooting I inadvertantly had the fuel pump relay and engine control relay swapped, so it still wouldnt start. Swapped them back and she fired right up. Thanks

Tiny
Dcraig10004
Mar 20, 2013.