Electrical system problem
 

My 95 C280 pops fuse number 26 as soon as power is applied to the system. This fuse is 7.5 amps and it protects the SRS MIL Convenience Control Module
[ Power Windows ], power seat relay module, Cellular phone. I have lost the use of the sunroof, windows, seats. Has anyone had a problem like this and if so was it the Convenience Control Module? I've tested the relay circut and it appears to be fine.

Mike

You will need a wiring diagram and someone who knows how to read it. Does the fuse blow immediately and leave splattered metal on the inside of the plastic body (assuming this is the kind of fuse loaded)? Or does the little fuse element just crack, maybe after a second? This might give some general clue but really you will need the diagram.

Mike

Electrical system problem
 

I followed your instructions Mike. Disconnected the CF Control module and still blew the fuse. I then diconnected the ESA relay and still blew the fuse. Decided to hook up an amp meter to the fuse location. Recieved a reading of 225 amps. Tried to operate the windows, sunroof and seats. All functioned as normal. During this test the amps fell to 150. An indicator light on the dash came on for the SRS. I shut the car off and then started it back up while timing the lit time of the SRS indicator light. According to my manual the light shuts off after two minutes if there is a non-crash related fault present. The light shut off at the two minute mark. I then shut the car down and restarted it a number of times. Amp reading fell to zero, all systems function as nornal and the SRS only stays lit a few times beyond four seconds. It is suppose to light up for four seconds at start up, indicating that the system is functioning properly. I thinking that the problem is located in the SRS control module.

It appears to me that those are the only 2 "sides" to that circuit. So if you unplugged the CF control module and the ESA relay and that other relay similar to the ESA (power seat relay I think) and the fuse still blows then the problem would have to be on the SRS side (see bottom of page 26 in your wiring diagram, fuse 20). I question your meter readings of 225 and 150 amps. Those currents are way beyond the max range of most multimeters. 150 amps would most likely melt the probe wires on any multi meter. There are some special clamp on meters that use a hall sensor to measure large DC currents (not the regular AC clamp on kind) but I doubt you have one of those, and I don't think the wiring of your car can handle 150 amps other than the big wires to the battery and starter. Maybe 22.5 and 15A? Anyway, I agree the problem seems to be on the SRS side and I know nothing about that other than there are explosives involved so I would recommend going to the dealer at this point. I assume there will be some codes they can read. At least you didn't blow money on a CF module.

Mike