Crystal Cranks

I have my car in a carcoon for the winter connected to the battery charger, went out to the garage this morning to see the spoiler raised fully and the spoiler motor still running and the not so nice sound of the spoiler gears eating themselves.

Only way to turn it off was to disconnect the battery.

Reconnected the battery and the spoiler motor stayed off, then turned the ignition on and lowered the spoiler by the switch in the car ok, then tried to raise the spoiler with the switch but would not raise because the gears are shot and are slipping so I helped the spoiler by hand but once it reached the top it would not switch off again.

Apart from needing new gears

1. What would have caused the spoiler to come on by itself when the ignition is off?

2. Would a faulty "up" microswitch cause this?

3. Any Rennlist help on what to look for would be appreciated.

Vandit

Strange... As far as I know, the spoiler switch doesn't even work w/ the ignition off.

911wings

open your deck lid and take the black plastic cover off on the left side, that's where the microswitches are located and sometimes debris can build up and interfere. I had a problem with mine sporadically going up and down (when the ignition was on, while driving) until i clear out some pine straw.
short term fix is to put the spoiler up and pull the fuse under the front hood.

justin-in-athens

Sounds like you have three problems, or two at the least.

Check both the microswitches that indicate spoiler position.
The motor/gears pretty commonly expire--available used, expensive even on ebay.
The control module under the passenger seat sounds like your root problem. There is also a relay located right next to it under the seat that could possible be getting stuck open.

Good luck!

Andy Roe

Also check the connector where the wiring from the spoiler connects to the car - it's on the right had side around the oil filter area to ensure its clean and properly connected. Mine was dirty and the symptoms were that when the spoiler moved up or down automatically the motor kept running and grinding the gears. Both micro switches were fine.

jcs_911

Wow. This sounds strangely like the time the starter motor on my car was engaging while the car was parked overnight. The first couple of times it happened I just thought the car rocked forward on its own. It moved maybe 2-3 inches. The last time it happened it moved the car forward about 4 feet into the stuff I had stored in front of it and burned out the starter. No one could say definitively "why". I ended up changing the starter and the electrical part of the switch just to be sure. That solved it (for now ). That and leaving the car in neutral now, too.

NineMeister

Fit a ducktail.....

Crystal Cranks

Thanks for the replies (even Colin's),
Ok I've a 90 so there are two units under the seat I have disconnected the aux unit and the ABS plug to make sure nothing is coming from here.
Reconnected the battery and turned on ignition, turn the switch to down and all seams normal.
Turn the switch to up and nothing will turn it off even turning off the ignition I have to disconnect the battery.
I even disconnected the plug at the back of the spoiler switch but no joy.
It will stop when the switch is put over to down but comes back on when you let the switch go and it returns to neutral position.

I opened the control unit and there is no obvious signs of anything burnt.

The mircoswitch does seam to be ok because when the battery is reconnected with the spoiler in the fully up position the spoiler will not work on the "up"switch is turned. Only when it is lowered normally and then raised it does not switch off.

So why does it not switch off?

On the plus side I found 3euros and 1pound under the seat that can go towards the cost of fixing this.

Crystal Cranks

I have a replacement control unit ordered, both micro switches tested OK at the control unit plug.
From what I can see the control unit has 12v constantly ON at pin 6 even with the ignition off can anybody confirm that? , I don't want to damage the replacement.

Harry Apps

The diagram looks that way - the CU is fed by a "30" which should be a direct battery supply. I guess it makes sense not to pass the motor current through the ignition switch. Presumably you've pulled the fuse (37) for the time being.

tcsracing1

did you use viagra instead of fuel stabilizer?

Crystal Cranks

Finally got a replacement control unit off e-bay after the second attempt, the first one I got was a dud.

Spoiler is working as it should by the switch but have yet to test the speed function.

But the gears are toast they are worn and are slipping when raising the spoiler, I thought I might be able to save them.

So I need to replace them, anyone that has a spare let me know.

Pic of what I need,

greg1990964

I only have one set of gears, but have spare control unit in my donor. Not sure where either control unit is on the 90' and 91' anyone?

Crystal Cranks

Control unit is under the right hand seat in my 90, (your passenger seat) Part No.911.618.112.00
You need to unbolt the metal plate it is mounted to so you can get under the unit to undo the nut holding it in place, do not try and pry it out.

It is under the dash on later cars but I'm not sure when this changed.

Harry Apps

Just (yesterday) finished rebuilding a spare one to swap on mine (new bearing and re-grease (+PTFE). Are you sure the gears are stripped - the unit is sealed and I found that, when mine slipped, the casing was split allowing the worm gear to move away from the pinion gear. Could be repairable.