Spoiler not going down
 

Hi,
I just reinstalled the stock deck lid on my 1991 964 yesterday.
Also had to reconnect the control unit (behind glove compartment) and also
pop in a 15A fuse in the fuse box.

Manually the spoiler works & also rises at speed although it does not retract when coming back to a standstill.

I've checked the micro switches in the tail for function and they are good. The control unit in the cabin also clicks when the spoiler hits the max and min travel so I know the signal is at least getting to the control box.

I'm also getting a spoiler warning light on the dash at startup although it goes off as soon as the car is over 5mph or so...

It seems like everything works except the signal that the car is slowing down isn't getting through.

Maybe the fault just needs to be cleared for the system to function properly?
Anyone been in a similar pickle?

Thanks!!

My 91 964 tip car spoiler does exact same thinghope someone knows

Simon got some good advice on Rennlist around this problem...check it out.

The only part I can contribute, is the spoiler light at first start is normal... it should go out after driving a few metres...

As for the rest.. ????

This might help perhaps?
http://forums.pelicanparts.com/porsche-964-993-technical-forum/388985-help-retractable-wing-wont-go-down.html

Scroll down to see a post from "colo964"..
Mine had that "morning wood", too. It turned out to be a bad controller PN 964 618 212 00(little gray box under the passenger seat). I got one from Oklahoma Foreign for about $100 (also try Parts Heaven or EASY in the Bay Area).

This thread on another forum suggests the same, but like all "problem" threads, no one ever follows through with the fix or what they found to be the fix..
Spoiler won't go down - Rennlist Discussion Forums

I had the same problem.....
Then I bought one from France !
Now it goes down every time !!

Cheers guys! Thanks for the info.
I've looked at the threads on Rennlist and even emailed with one of the
members who is a electronics wizard. So far all the tweaks haven't worked.
I've broken into the control box and replaced a bunch of individual components on
the circuit board. Started with the transistors and I'm now onto the diodes.

Will give it a little more DIY troubleshooting then get another unit.
I didn't know about Oklahoma Foreign, Parts Heaven or EASY so will try there.
If I can get a controller for $100 that would be good news.

I lost control of the cabin heat two days ago and traced it back to one of the servos. Luckily I actually managed to fix a servo. It's only 30 mins work and just needed some contacts cleaned. Thank goodness because those cost up to $500.
I'm hoping my luck there will translate over the spoiler.

Control unit sent to:

Systems Consulting
3520 Maple Ave
Manhattan Beach, CA 90266

Should be able to repair for $135.

I'll update later after they take a look at it.

problem solved
 

The unit was fixed by Loren @ Systems Consulting.

Do you happen to have a phone number or email for Loren? I'm not finding them on the web. I have the same problem.
Thanks!

I beleve that Loren is a Pelican (Lorenfb). PM may work.

Found site, Systems Consulting...Automotive Electronics

Awesome, thank you! I'll give them a call on Monday.

I spoke with Systems Consulting, very helpful and knowledgeable. I was able to get the spoiler to close using the manual switch today. It had not worked previously. The motor sounded crunchy, which can't be good. Does that indicate the bearing should be replaced?

Are there any special tricks to getting the control module out? I located it under the seat, but it seems to be fastened on the bottom to the metal plate.

The bearing on the worm drive cable normally needs replacement by this age. The cable's rubber sheath usually has cracks in it that allow water inside the cable/bearing, making for a very rough running mechanism. The "wall" is also an item that develops cracks and consequently needs changing out every couple of years. There have been some threads that have indicated some difficulty in closing the spoiler when the wall had degraded to a certain point. Segments of the degraded wall catching on other segments when attempting to lower it. There are threads walking you through the process of replacing the drive bearing and wall on the spoiler system. Fortunately, I have never needed to remove the control module so I can't help you there....sorry. Cheers

My spoiler was acting funky. Not always going up or down, going up slowly making the spoiler light go on. I cleaned the plug for the motor under the rear deckled and the contacts on the spoiler controller under the dash with electrical contact cleaner. (on my 91 C4). Fixed the problem and made me fell smart. ;) Easy fix to try first.

I like the sound of that.
Is there a diagram of sorts somewhere of this system?
I'm not finding anything in the two manuals I have: Bentley & 101 Projects.

My rear spoiler was stuck in the up position and will not come down.
27 years on the original unit is pretty good so I just sent it for repair.
I sent my control unit to Loren. He got it fixed. I am a happy customer.

He can bench test and repair the unit.
If the bench test confirms there's nothing wrong, he charges a minimal bench test fee.

Systems Consulting
3520 Maple Ave
Manhattan Beach, CA 90266

Is there a specific relay for the rear spoiler? NOT the controller under the glovebox but a relay in the fuse/relay box under the bonnet?

Thanks

RML