964 spoiler doesn't retract

[simonstorey]

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 perfectly. The spoiler 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 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 car is just telling me to speed everywhere, although I don't need much help with that

Maybe the fault just needs to be cleared for the system to function properly?
Anyone been here...done that?

[Drisump]

Your in the wrong forum for the best advice, this one is for the pre 964 generations. I do have a 993 though and understand the issue. If the spoiler is performing well manually and properly deploying automatically it's good news that the expensive bits are probably fine. I'm not sure of what circuitry is used to automatically retract below 5mph. There must be something that generates a retraction order at a measured speed of 5mph.....don't know if that would be the speedo itself or a unit that measures the final drive pulses and sends a signal to the spoiler drive motor. Like I say...wish I had better input for you. Cheers

[simonstorey]

Thanks for your reply!
I'm still relatively new to this forum although it seems that posting 964 questions
in the general section gets a better response. There are usually about 1/10 the number of members viewing the 964/993 page at any time.

Yes I agree that I seems the 5mph signal is not getting from the speedo to the spoiler control box. Or from whereever to whereever? It could be anything.

The question is then how do you diagnose and repair electronic problems. It seems slightly harder than looking for a loose wire somewhere?
Time to call the professionals?

Cheers

[Drisump]

Not to denegrate Pelican, but in the realms of the 964/993, Rennlist is a much more active site. Perhaps you should try there. Cheers

[simonstorey]

Originally Posted by Drisump

Not to denegrate Pelican, but in the realms of the 964/993, Rennlist is a much more active site. Perhaps you should try there. Cheers

No worries.
You're the second person to mention that...
Cheers