Eldorado Mirrors Adjustment

[Roadcapt]

Hello Folks

93 Eldorado Mirrors will not power adjst all ways ie... one up but not down one out but not in. I remember on my 03 H2 we cleaned the motor contacts. Do we do that here? If so where they at?

Thanks

[Cadillac Jim]

In the 1997 FSM, pages 8A-141-10 (switch) and 8-141-11 (motors), the possibilities are bad switch contacts (most likely) and possible relay contacts in the MMM. I say the switch is most likely because spilled drinks or other debris over the 19 years of life of this car, so far, are more likley to cause switch problems than the MMM or the motors are to give problems. I say possible relays because the switching inside the MMM can be transistors driven by electronics and relay coils are not shown, just switching to explain polarity reversal on teh motors to allow one motor to turn a mirror both up and down, or left and right.

Reading and posting the OBD codes may clarify whether you have a switch, wiring or module problem.

The MMM is under the dash above the brake pedal. If it doesn't click when you do something with the mirror controls that works, it doesn't have mechanical relays in it. One guy on the floor listening through a tube from a roll of paper towels and anther working the mirror switch will tell that tale. But it looks like either you need to clean and tighten some connector contacts or grounds, or the switch is bad. I don't know whether the switch can be disassembled for cleaning or not.

[Roadcapt]

Thanks, this gives me a starting point will get on it. Just sighned up for an advance auto body an paint course at local cc might be able to slip eldo in for some hands on!!! need all this little mess done..

Be Safe

[rockfangd]

just out of curiosity What is the module on the underside of the driver seat on the memory featured ones. I have a couple of the modules and all of the wiring goes into it for the memory. unit does not exist on a non memory model. note this is on the 96,97 and other newer models

Also I had the same issue with my 96 ETC and could not figure it out. All wiring seemed fine. I forget which directions didnt work but when I replaced the mirror switch (which is common) it did the exact same thing. I think it even threw a code for it in the MMM portion or the diagnostics. Never tried replacing the MMM though. just let it go

[Cadillac Jim]

The module under the seat is the memory seat module (MSM). The memory mirror module (MMM) is under the dashboard above the brake pedal.

The OBD codes would be a good thing to have. Very often having these codes eliminate a lot of guesswork.

If a motor was bad, the mirror would not move up/down or left/right. If it moves one way but not the other, then voltage of one polarity but not the other is being applied. The module determines the polarity and applies the voltage. The switch assembly on the driver's door arm rest operates the module. The motors in question operate one way but not the other. Thus the problem is the switch, the wires between the switch and the module, or inside the module. Since the MMM is almost certainly solid state (but the EBTCM contains one or two relays!) that operate the mirror motors (very probably with what is known as an "H-bridge" that uses transistors or MOSFETs, not relays) and rarely fails, this leaves the wiring and the switch.

I would not entirely rule out a break in the wiring. The point at which the wiring flexes at the door hinge is a point to look at, if the wiring does not check out. I had an electric window problem back in the dark ages that was caused by such a wiring break. I've never heard of such a wiring break in a Cadillac of Northstar vintage, however.

If the wiring is good, and cleaning and tightening the connectors on the switch and MMM doesn't do the trick, then a new switch assembly is in order.

[Roadcapt]

Man That `brecks it down huuh

[rockfangd]

thank you. I love learning things. I agree before you go any further pull the codes.

If both mirrors dont work in the same way it is either switch, wiring, or MMM issue.

Code should help if there is one

[Roadcapt]

no codes, the switch is bad. took it apart today an cleaned micro switches still no down or out on both mirrors. multi meter showed no voltage from switch.

thanks for the input