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sunroof operation question

6103 Views 22 Replies 11 Participants Last post by  Bknesal
i just recently acquired an 87 300TD. Woohoo!

anyway, the sunroof switch seems a bit weird...
to get the sunroof to tilt up i have to PUSH UP on the switch... which i guess is normal... to get it to close from the tilt position i PULL DOWN on the switch, again normal right?... but if i hold the switch in the PULL DOWN position the sunroof proceeds to open fully... so its hard to get the sunnroof to close fully from the tilt position... i'd have to check outside if its fully closed and not partly on its way down to open rearwards.

anyway, from a closed position, if i want it to open rearwards i'd have to slide the switch rearwards... again normal right? but if i wanted to close it (without opening the roof fully rearwards)i'd have to PUSH UP on the switch, as with tilting, coz if i slide the switch forward, toward the windshield, the sunroof would just continue opening rearwards.

what gives?
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Sliding the switch forward should close the sunroof.
Yeah it does... if I hold my switch in the down position when the roof is slid open it will close it. The only position that will slide the roof open is sliding the switch back.

If the switch is pulled down to close a tilted roof, it will just close it and not do anything else if held down.
hmmmm, so is there a control unit for the sunroof besides the switch?
Well sort of. There's a relay mounted right on the sunroof motor assembly (which is located at the base of the left c-pillar). Access the sunroof motor assy by removing the left side trunk lining. Have fun crawling into the trunk. Been there, done that, bumped my head. Removing the motor assy is a nasty job because the roof panel drive cable runs *through* it. Since your motor still works, though, you're miles ahead.
thanks for the reply.:)

i don't have to worry about bumping my head since i have a TD. :) the motor assembly is accessible once i remove the spare tire panel. :)

i'll check out that relay

thanks again
You need to time the sunroof. It is out of synch. There is a procedure in the 124 shop manual. It deals with a 3mm guide pin IIRC and and the white knob on the motor assy. Good luck.
autozen said:
You need to time the sunroof. It is out of synch. There is a procedure in the 124 shop manual. It deals with a 3mm guide pin IIRC and and the white knob on the motor assy. Good luck.
I agree, it is a simple job.

Mine does the EXACT same thing. Let me know what you figure out.

From "Model 124 Service Manual"

1. Make centering bolt (see Roof1.jpg)
2. Remove trim on rear fender inside left.
3. Push actuating switch to "Lift roof" until the sun roof panel is completely lifted.
4. Make adjusting knob into adjusting position
(pull out up to stop and push in for approx. 3 mm)(see Roof2.jpg)
5. Turn adjusting knob until the centering pin can be completely plugged into centering bore
and the notch on knob points in direction of bore.(see Roof3.jpg)
6. Push adjusting knob and remove centering bolt.

CAUTION! With centering bolt plugged in or adjusting knob pulled, DO NOT operate sun roof motor,
since otherwise the control unit may be damaged!


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My sunroof will not tilt all the way up. The left side moves up a little. It slides open & closed correctly, except that I have to use the tilt part of the switch
to get it exactly closed. I thought I had a part of the mechanism broken,
but could it a timing problem?
I love this web site!

Johnny C!
Hey Bombo101,

That worked! Yippee!!!!


sorry, couldn't reply for a while. was busy with deadlines! :)

jcochran good to hear you solved the problem even before i've read the solution.

thanks to all who replied. :)
wouldn't know what to do without you 124 guys!

thanks for the pics bomb!
ok, i tried it but the adjusting knob refuses to turn, i didn't want to use too much force coz i didn't want to break anything...

is it really that hard to turn? or is something jammed up good?
How do you make the centering bolt? that looks like an allen key of sorts...
when i pull on the knob to put it in adjustment position the knob turns freely, with absoulutely no drag... nothing happens with the centering bore, its as if nothing is turning inside to allow the adjustment tool to be fully inserted...

what is the purpose of the white knob anyway? what does it turn?
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