Thanks to Jamie Biggs for the orginal write up which appeared on the VWvortex, contact him if you need an A3 (and possibly Passat) moonroof assembly here
Well, the sunroof in my black Corrado was broken and while I had the headliner out for cleaning I decided to get my sunroof working.
My drivers side guide was snapped in two so I figured I'll just get a whole new assembly with glass. Its a pretty easy swap, just time
consuming. Much thanks to Bill (G60247) for letting me use his Digicam to snap a few pics of the process.
Here's the moonroof assembly and switch fresh picked from a '99 Jetta at the boneyard
Step 1: Remove sunroof motor cover, sun visors, A pillar trim (be careful and make sure you undo the metal clips from the seatbelt
track), sunroof headliner moulding, and undo the tops of B&C pillar covers so you can slide the headliner out looking like this:
Step 2: Remove the 4 water runoff tubes from the sunroof assembly
Unplug sunroof motor wiring harness and unbolt the sunroof assembly from car. There are 10 bolts that hold it in, 3 along the 2 sides of the car and 4 in the front along the windshield. The bolts are 10mm in size and look like this:
Once you have the sunroof assembly unbolted from the Corrado, drop the front down and slide it towards the front of the car to
remove. Having someone else around to help right about now makes life much easier.
Some side by side pics of the sunroof and moonroof:
Everything looks good, bolt holes all match.
Step 4: Lift the moonroof up into the hole in the Corrado roof, an extra set of arms helps right about now too
Thread one or two of the bolts in along the front edge of the moonroof just to hold it in place, these bolts are only going to be there
temporarily so there is no need to tighten them up.
Now, the A3 glass doesn't exactly sit flush along the roof of the Corrado,
So I'm gonna show you how to straighten this problem out. You will need about 16 washers and the bolts that held the moonroof in the
A3 (you did get those bolts, right?) The A3 bolts are longer than the Corrado bolts as you can see here:
The whole sunroof assembly needs to sit a few mm's lower in the corrado so we're gonna use some washers as spacers to get the job
done. I had a bag of washers laying around from another projsect, but you might want to make a trip to Lowes or Home Depot and
Wendy's right about now. I don't know the specs on the washers I used, they were in a clear plastic bag marked 'flat washers,
hardened, 50' but here's a picture of 2 next to one of the A3 moonroof bolts:
Along the front edge of the moonroof assembly (parallel to the windshield) place 3 washers in between the moonroof and the body of the Corrado like so:
In that pic there are only 2 washers but I ended up using 3 later on. You want the washers to line up with the bolt holes so you can get the bolt through. You only need to use spacers in the front holes of the moonroof track, the back 4 (2 on each side of the car) don't need any. I also only used 2 washers in the front holes along the sides of the track (perpendicular to the windshield)
Sorry, the pic is out of focus, but you get the idea.
So (3 washers times 4 bolt holes = 12 washers) + (2 washers times 2 bolt holes = 4 washers) = a grand total of 16 washers used. Now
the A3 moonroof fits the best it ever will. The curvature of A3 moonroofs is slightly greater than that of our Corrado roof, but its no big deal.
Step 5: Now comes the fun part, you get to play with solder and fire. Because I am using the motor from the A3 car it is easiest to use the A3 switch too. Believe it or not, '91-'92 Corrado dome light wiring plugs right into the A3 switch. If you have a '90 I don't know what to tell you, just use the Corrado motor and switch maybe (the Corrado motor will bolt onto the A3 mechanism), or do some custom wiring. If you have a '93-'94 you might not hve to do anything but plug it in, I don't know. The only Corrado dome light and sunroof switch wiring I am familiar with is that of the '90-'92 cars. In the pigtail coming from the A3 moonroof motor you will see a brown wire, duhh, its a ground(-). Attach it to one of the 2 brown wires going to Corrado switch. In the A3 sunroof motor pigtail you will also see a red wire, connect it and the black/white wire from the A3 switch to the black/yellow wire from your Corrado, these are all switched positive(+). There was a green wire from the A3 sunroof motor that I didn't use, I have no clue what it is for. Thats all for the wiring, pretty easy, it only took me a few minutes with a test light to figure out. I used solder and shrink wrap to attach the wires, that should hold up a long while. Plug everything in and see if it works, if it doesn't, well... I don't know what to tell you. Get out a test light and do some thinking on your own.
Step 6: Now is a good time to clean you headliner. Castrol Super Clean on a clean rag works well. Put everything back together.
The A3 moonroof switch
The A3 headliner slider
As you can guess I have some left over parts for sale, like a beautiful black sunroof panel, sunroof motor, sunroof switch, sunroof
headliner moulding (cause I used the one from the Jetta), and an inner grey sunroof cover. I'll post em in the classifieds.
Please post any questions/comments/concerns and I'll do my best to answer them.
