GKT, not sure why you are asking, but your +4 should be similar to my 4/4.
I had real trouble with my washer pump shorting to earth a couple of years ago.
The culprit was under the dash as the loom goes over the steering column.
You will have to expand the pic to see the damage.

[Linked Image]

4/4 Ivory 4.1:1 axle, Mercedes A200 AMG