'78 911 SC Power Mirror Woes

[sunshinestateR]

Howdy folks,
need some advice/ideas on getting some power mirrors on a '78 911 SC to work properly...the gremlins are killing me!

Here's the car's history/symptoms:

I'm about to complete a full restoration on the car. I disassembled the whole thing about a year ago and of course made the mistake of not noting whether or not the mirrors were working properly then...

So far I can find no physical faults in any of the wiring. With the car's original mirrors plugged in I have power...switch selector to the left, driver side moves side to side when toggled, very weakly, won't move up and down at all...selector switched to the right, passenger side moves side to side also weakly, toggle joystick up and down it just clicks AND makes the driver side click ALSO...???

So...I installed another pair of USED but in GOOD condition '78 mirrors....
and then...selector switched to the left, driver mirror moves side to side, also weakly, but NO up and down....selector switched to the right, passenger side also barely moves side to side...BUT no more clicking on the driver mirror like its actuating both of them...

NEXT, I tried installing some working mirrors off an '87...these are the kind with the newer motor, glass attached with a lock-ring, and different color wires...
the plug is the same, so I plugged them in...

WELL...the '87 mirrors also move side to side this time, albeit a lot stronger...AND selector switched to the left, driver side, I now get movement when actuating UP and DOWN on the joystick!...EXCEPT the mirror only moves UP...even when you toggle down...on the right, passenger side, I get side to side wiggle when actuating the joystick...but no up/down...

WTF???

On the old mirrors you couldn't get ANY up/down movement at all...

What is going on here? I can't find any damaged wires in the wiring harness and all colors on the original mirrors and the used ones I bought match up? WTF?

COULD IT JUST BE A BAD JOYSTICK and/or MIRROR SELECTOR switch?

HELP!!!

[86 911 Targa]

With all of the uncertaincies you describe, a Bently manual
or equivalent will be required.

Once you have reviewed the circuit diagram, and determined
which connector pin(s) activates the L/R U/D functions, you
may want to test the mirrors off the car thereby eliminating
any body harness/toggle switch ect.... issues.

This jpeg is for the 1986 model year.

Perhaps the wire colors will match up for you.

Send me an email with any other questions/comments.

Good luck,

Gerry

[sunshinestateR]

Thanks. This may help. I will post further successes and failures, haha. I've got a new toggle switch on order, as my post searches lead me to believe they can get worn out and make things act funny. If anyone else out there cares to chime in, please do.

[Mysterytrain]

there are two different types of flag mirrors..the old style [ like on your 78 and mine] and the 'newer' type. The old styles uses one motor and a solenoid/clutch. The clutch switches the action from side to side, to up and down. The newer type uses two motors toget the same functionality...as shown in the drawing above. The newer style has a different mirror selector switch and joystick. {not totally sure about the joystick} Anyway, you can't mix old and new. I also think there might be some subtle harness/connector differences. The mirrors can be tested on the bench which helps isolate the problem. I had an intermittant clutch which drove me crazy in the end I had to replace the guts.

[Mysterytrain]

Need help hooking up electrical mirrors

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