Hey julius,
That year merc had two wiring schemes for the PWs, an early and late design. Both have a 60 amp fuse (#6) in the pwer junction block under the hood.
Then there is either a 30 amp fuse (#47) in the same box or a circuit breaker on the way to the central junction box.
Both have a 15 amp (#17) fuse in the central junction box. They also share an accessory delay relay.
The relay is controlled by a Gem (generic electronic module) module. I remeber seeing something about these going bad because of a leak in the windshield cowl on explorers.
All power goes to the master switch first and then to the individual switches on the doors.
If you are getting no power at the master switch, check the fuses/circuit breaker first, swap out the relay next, and then check the Gem module.
If that doesn't work following wires looking for a short is the next step. PITA!
Good hunting and let us know. :)
peppermrj
Friday, August 2nd, 2019 AT 5:26 PM
(Merged)