View Full Version : Electrical Problems

02-07-2004, 02:07 PM
Ok heres the problem.

I have recently bought another Sc (90 35th) and the problems started with the dimmer switch not wanting to go into high beam, this was an intermittant problem and when you pull back on it the high and lows come on as they should.
The other day the VMM and the ride control went out. I have change the relays,checked the 30 amp fuse in the dist center, check for power at the relays (ride control), and went as far as to change out the ride control ecm.
I have checked ground 100 at the column and have good continuity to the chasis. Check for power at the switch at the console and checked the bulb in the dash.

(1) Power at the switch = none
(2) bulb good

I know that the car isnt going into firm ride becuase of the feel and the absence of power to the relays in the trunk.
The 30 amp fuse in the engine compartment is showing 12vdc on both sides. The dash bulb gives no codes at all, nor does the diagnostic connector have any voltage.
I have another 90 model here so part swapping is not a problem, but personally I feel that is is something so simple that I will end up kicking my self in the end.
After using a snapon mt2500 to scan the car it has no codes on the engine ecm but will not communicate with the ride control ecm.
One last thing to ponder is that the cruise or horn does not work and that that the prior owner had the premium stereo pulled out and put an aftermarket on in without any amps (the original wires have been cut) no problem cause I have another for parts when I get around to it...

Ok guys and girls jump on this one becuase it has me totally confused and as I said before it is probably something very easy but I am overlooking it....


P.S. I have access to all the wiring diagrams for this car and have traced out everything that I can think of, which is what I have mentioned above.

02-07-2004, 03:53 PM
OK Brain Fart

G100 which is the ground that hooks to the sheild to the right of the steering column.
When it goes into the wiring harness where does it come out at in the engine compartment? I have looked these schmatics over and over till I get cross eyed and cant seem to find it.
Maybe too much tequila????

02-08-2004, 10:12 AM
there is a fuse link on the starter relay ..that powers the actuators..from the hard and soft relays... I don't think it's the problem ....the relays themselfs are... powered from the same power feed as the firm/soft switch...also powers the VMM ...the VMM is wired to the dimmer switch...so this path ..leads me to believe..that you have a power feed problem ..from the ignition switch.. to the VMM and ride control switch and hard/soft relays ....check fuse # 12 ..15 amp .. 3rd one down.. in the middle row ..and # 19 ..bottom right ..10 amp ..in the fuse block under the dash.. for power ..dave

02-08-2004, 04:51 PM
Thanks for the reply, but I have already checked every fuse in the car both in the cab and under the hood. One idea you mentioned that I havent checked is the fusable link but if memory serves me right if that one goes you wont have any power at all to the car. but I will check it out anyway. For some reason I am leaning toward a ground problem, why I dont know but its just a gut feeling.
Thanks again for the help, I was begining to wonder if I had everyone stumped here.

I have just come in from checking the coninuity on the wires that you have mentioned and apparently I have blown those fusable links somehow. I will have time to do the repair sometime this week and get back with further info as to if this has fixed the problem. If this is the fix then the fun starts, because something had to cause this to blow and it needs fixing, maybe age but I seriously doubt it. I would do it today but I have to get ready to go out to N.c. for tommorrow morning and the job take priority over this car, but it will bug the sh&* out of me till I try it.

Agaain thanks for the reply..

02-13-2004, 06:24 PM
Ok, After beating my little brain over this thing, I have finally created a temp fix.
I have chased all the wires concerned here and came to the conclusion that I do have a power failure somewhere in the system. The purple and yellow wire that supplies the relays for the arc and the vmm had no power. So after runnig in from the fuse panel under the hood and redoing all the grounds I could find I finally tooka 12vdc power source (ignition) to the steering sensor on the column and suddenly everthing went to working.
Now I know this is temp but tells me that the problem has to be before the steering sensor if my theory is right. Does anyone have any knowledge as to where a possible fault in the system could be as in maybe a harness pinch.
Any help would be greatly appreciated, as I only got one resopnce to the initial post.