Electrical problem after motor changed

[Tismael711]

1989 325is motor died, bad head...so i had mechanic swap in 1990 motor with 104k. Now i have no electrical power to anything in the car. Battery was jumped but still no lights, no horn and of course the car wont start. Any suggestions?

[e30mpg]

check your grounds

[dnguyen1963]

Was he a BMW mechanics? Regular mechanics might not understand how important the grounds are to BMW car.

[Danny]

Here's an idea: go back to the mechanic.

[Tismael711]

yes he works exclusively on bmws.....mostly E30s.

[Gregs///M]

Start with the engine to chassis ground. Mounts from oil pan to frame rail on drivers side.

[Tismael711]

any other advice? ground appears good

[dnguyen1963]

Ok, you'll have to be very methodical to solve electrical problems. The first thing I would do is to verify that the starter receives juice from the battery. I would then verify that all fuses/relay receive power and that power go to their intended targets. If everything receives power then check the coil, spark plug wire, Dist/rotor, and DME. Has your mechanic verify the timing on your engine?