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ejm918
08-11-2013, 05:02 PM
I have a 1990 Celica GT hatch. It does have a sunroof, however it doesn't work. I checked the fuses and they seem ok. So I'm thinking either the switch is bad or the motor is bad. So is there any way to check any of that with out ripping a lot of stuff apart? and what would more likely be the issue?

Shadowlife25
08-12-2013, 01:19 AM
The issue is most likely the switch itself. Unfortunately this is a common occurrence with older vehicles since they did not use relays. The switch IS the relay. :(

I would say to go ahead and replace the switch when you are able. I myself need to do the same thing. When I do, I will be wiring in a relay to make things easier on the electrics.
(Though if the switches lasted 20 years to begin with, I am sure they will be ok. lol)

93celicaconv
08-12-2013, 01:03 PM
Agree with Shadowlife25. You can pull the switch out of the headliner easy enough. Once you have it out, you can check it:

- on the hot wire going to the switch, make sure you have 12VDC available when the ignition key is in the "RUN" position.
- on the ground wire side going to the switch, may sure you have continuity from that terminal to a good body ground
- with the ignition key removed, push the switch in one of the two positions and check that there is continuity between the hot & ground terminals on the switch.
- if there is contunuity, check this again, but this time with the ignition key turned to the "RUN" position (you could also jumper these 2 terminals if there is no contunuity and see if the sunroof motor will operate

There actually is a relay in the sunroof control system. It is a small box mounted between the headliner and the roof, right next to the switch assembly, and you can see if when you remove the switch housing from the headliner. There is logic in that relay box regarding stopping the sunroof on close about halfway through the close move. It also stops the motor at the end of travel (unlike a power window regulator). Sometimes this relay box goes bad. I have several of them because they have been known to fail and I don't believe they are available anymore, but my several spares have not been tested (salvage yard specials).

Physlis
08-13-2013, 03:28 AM
I did a little testing today on ejm's sunroof controls and pulled the switch housing (didn't see this thread till just now though). When I hit the "up" switch I can hear a "power draw" but nothing moves, hitting "down" or either slide control doesn't make any sound or indication of function. I then tried to manually adjust the motor with a flathead, got about a 1/8 of a turn and it quits. Sunroof is a little loose when pushed up on. Next chance I get I'll break out the multimeter and check the power the right way.