flyweight

Folks,

I just had my 97' 993 Cabriolet delivered today, after winning an online auction. My excitement quickly turned into distress when I couldn't auto-open the top (the seller didn't disclose this and I was too stupid to remember to ask for a video). The top unlatched fine but didn't not retract (and no further motor sound). Not a fuse problem as the latch motors share the same fuse and they are fine so far. Am I looking at the main motor problem, or possibly controller? Your suggestions are appreciated.

CabrioArtie

I would start with pulling the carpet behind the rear seats back and see if the motor is running while pressing the switch. If it isn't running, test and see if it/s getting power. With these results the next steps can be decided.

The rear motor doesn't make a lot of noise so it may be running even if you don't hear it.

Do the latch motors stop running after the top unlatches?

PNW993

Congrats on the delivery of your 993! I have a cab and have had a similar issue. Try unscrewing the panel around the parking break (its only a couple of Phillips head screws); it very easy to remove. Once removed you should see a switch that makes contact with the parking break when the parking break is in use. If the switch is not making contact, the top wont work.

I used a shim to keep the switch from popping out since it kept happening. Since I put the shim in, I haven’t had any issues. I hope this helps.

PNW993

If the motors continue to run but the top doesn’t go down, its possible the previous owner converted the top to manual operation. You can a thread on it here: https://rennlist.com/forums/993-foru...eration-2.html

I converted mine to manual operation and I’m pretty happy with it.

flyweight

Thanks folks! So I should take a look at the motor first. If it runs then most likely the seller was doing manual. If it does't run, then I should look at the parking brake contact. Is this the flow I should follow for now?

systemsc

There's a description of the Cab Top diagnosis found here under Porsche/Cab Top; https://www.systemsc.com/problems.htm
Repaired ECUs are available on an exchange basis.

flyweight

My latches lock and unlock properly. The top just doesn't retract after it unlatches. Would this still be ECU-related? Thanks.

PNW993

One way to quickly check if you cab is setup for manual operation is to unlatch it, then get out of the car and try to manually retract the top. If the top wont move, I would try the ECU.

flyweight

That's good info. Thanks. There might be possibility that the seller retightened the screw before the sale to hide that fact.

Update: My situation is now worse. I had my son keep the Down button pressed, I looked at the motor under the carpet behind the rear seats. There is no sound coming out of the motor. However, when I tried to latch it by pushing the Close button, nothing happened. We couldn't get it to latch now!

Tried reseating the fuse etc. Didn't make it difference. But in this position, pushing the down button makes a clicking sound while the closing button no sound. Before I did this experiment, once it was unlatched, pushing down the down button produced no clicking sound.

Thoughts?

flyweight

Sounds like the ECU board may be my next step? Without the latches working, making the top manual won't help.

PNW993

I would check to make sure the parking brake is making contact with the switch:
https://rennlist.com/forums/993-foru...-location.html

flyweight

Will try that first. Thanks.

CosmosMoon

you aren’t totally stuck in this almost- closed position BTW, you can manually get it to latch. There are two holes in the top by the front edge, inserting a flat-head screwdriver and turning … a lot! … will operate the latches. It’s tough to figure out what to do with the cover on, so if you’re forced to do this, then for the first time I’d unscrew the cover and pull it off (it has IIRC two Philips screws and some push-clips) and then use the screwdriver on the latches. Once you’ve done it once with the cover off you’ll get what’s happening and you can leave it on for next time.

I did this once when I stopped it just before it closed all the way and the micro-switched got out of sync.

systemsc

The 993 Cab Top ECU requires both the parking brake AND the oil pressure switch inputs at ground.

abiazis

you can use a low powered drill to turn the motors to open and close…best with trim removed - easy off and on for the trim with visible screws….