ChemMan

Hi Everyone,

From what I see many 996TT owners have had issues with their rear spoiler. I am hoping to get some help in fixing mine. I have read several threads so if I am wrong in what I am writing, please let me know.



First, the current situation. My car is a 2001 996TT:



The switch for the rear spoiler is not lit up.

The wing is in the down position.

When I press the switch, I hear a click noise but nothing happens.

There are no apparent leaks.

The pentosin fluid in the rear is approximately half way in the rough portion of the "cold" part of the dip stick.

I am not sure if it matters but the pentosin fluid in the reservoir in the front is close to max.

I have checked the fuse and it is fine.



My understanding is that the next things to check would be the micro-switches, the electric motor, and the hydraulic portion....not really sure about this.

Since the light is not on, could it be a problem with the microswitches? Is there a way to test the microswitches with a multimeter?

If not, to test the electric motor, how exactly do I do this? I see a harness I can unplug but if someone can give me instructions on how to do this, I would appreciate it.



I am hoping that since there is no apparent leak of hydraulic fluid that the issue is with the motor or microswitches. I know many of you feel that it is better to replace the spoiler with an aftermarket unit or place the wing in a fixed position. Before it comes to that, I want to at least give fixing this a try.



Thanks in Advance!


(I posted on another forum so sorry about the repost...did not get a reply there)

rmc1148

Try search and read all you can most everything is covered there and on other forum search.

Macster

AFAIK there is no way to check the fluid level in the spoiler system. It is a sealed/closed hydraulic system. If there is any signs of fluid wetness there is a leak and this is a sign the spoiler will soon not work right.

Thus I believe you checked the fluid level in the power steering reservoir and the clutch reservoir. Good for you but these do not have anything to do with the spoiler's hydraulic system.

Oh, keep an eye on the fluid level in that front reservoir. One sign the clutch slave cylinder is bad is this reservoir collects fluid which eventually leaks out and fluid stain will appear on the top of the plastic panel that covers this reservoir.

If you press the spoiler button and you hear any noise but the spoiler does not go up and there is no warning light on the dash along with a warning message about the spoiler I'm not sure what to make of this.

My observation is if the spoiler is commanded to go up and does not a warning light comes on. Something after a time expects to see a limit switch open indicating the spoiler has left the non-deployed position.

Furthermore this same something expects to see a limit switch closed indicating the spoiler has reached its fully deployed position.

Have you tried removing the spoiler fuse (Row D, position 7 IIRC, but check the fuse list in the cover of the fuse box) and operating the spoiler either manually or by driving the car up to and beyond the speed at which the spoiler deploys?

See if you get the warning light, the warning message, and hear the alarm sound.

Be aware that this fuse also is for the engine compartment lid and this will not open with the fuse removed.

ChemMan

So my power steering fluid is good

I checked fuse D7. It was fine. I will try removing it and driving like you suggested.
I was also thinking about the relays. Perhaps the relay to initiate the "up" movement is faulty. I am not sure how to check the relay but I could swap the "down" relay and see if it does anything.
The perplexing part is that I do not have the warning light. It seems like in a majority of threads I have read, this malfunction light is present. Even the troubleshooting guide in the Essential Companion only lists options with the light on.

The components of this system then would be:

1. The wing and associated lift mechanism
2. The electric drive/motor
3. The hydraulic portion
4. Microswitches
5. The two relays by the fuse box
6. Fuse D7

Am I missing anything? If not, the issue has to be in one of the six above.
Macster,
Thanks for replying!
Mike

"02996ttx50

the three things that fail most often in order of frequency of occurrence are:

low fluid in the rams
bad microswitch(s)/connection
pump motor failure

given that you initially checked the fluid level of your power steering, rather than the rams of the spoiler mechanism..

check for leaks at or near the bottom of the rams where the banjo bolts are. if they are wet/moist? that will be at least a good part of the issue, if not it entirely.

Macster

There's the dash switch to raise/lower the spoiler.

And there's the signal from the DME (or the instrument cluster controller or whatever controller sources this signal) to the spoiler electrical control system to raise is not making it to the spoiler electrical control system.

Thus the spoiler does not go up but the rest of the system does not recognize an error condition because there has been no arming signal from the DME or whatever sends this signal.

IIRC from the wiring diagrams there's a relay (or two) involved.

I do not know if I'd swap relays they may not be interchangeable.

I do not know if one can bypass the relay, bridge it like one can for say testing the fuel pump.

Given the rarity of your car's spoiler situation I'm thinking you need a Porsche tech involved.

Messing around with the DME (or instrument cluster controller) is risky. One static discharge could render an otherwise perfectly good DME or instrument cluster controller junk.

ChemMan

I undid the covers on the bottom of the rams and they looked dry. I did it last weekend. I will look again. It might be easier to switch to an different rear spoiler especially if this is a reoccuring problem. I will look at it for a bit more before deciding. Cost of repairing the existing system vs new spoiler plus cost of paint and installation.

wross996tt

you might like to read through this entire thread

Kevinmacd

The micro switches are on the passenger side ram. You have an upper switch and a lower switch. On the ram you will notice a plastic cover. Take the cover off and the micro switches just pull out. Check them with a meter by pushing on the actutor. Ican tell you bleeding this system is a pain, due tot he limited amount of pentosin in the system.
You can pursche the whole system ready to go with all the electrical and hydraulics in place. It takes about 45 minutes to repalce it. The only draw back is the replacement system caosts about $1300.

"02996ttx50

as wross has posted the diy's for the hydraulics re-bleed.. i would take a good look at them, and if you are capable or have help as i did/do.. i would endeavor to have it fixed myself for a bottle of pentosin/lucas stop leak and an hour ( or two, tops ). if all else fails.. there are the fixed wing bolt kits ( for 150 on ebay ) or .. you know the choices im sure.

provided ( should say IF ) your fluid in the rams is low. it is the numero uno culprit of spoiler malfunctioning, particularly when it is intermittent. GL w it

ps i have a ten yr old turbo. the spolier has been repaired ONCE.. all AOK. years later

ChemMan

I am going to check the microswitches this weekend (hopefully). If that is a bust, I will look into re-bleeding the system.

Thanks for all the help. I appreciate it.

"02996ttx50

that the rams may be dry? could literally mean it was out of fluid. if so..? then you have every chance of being able to refresh/re-bleed them. it's always a minor victory when i hear of a successful DIY repair on 'em since they seem so daunting. until you get them apart. GL w it!

ChemMan

Success....kind of....I removed the plastic covers on the bottom of both rams. They had a small (small) amount of what I would describe as grease like as oppose to hydraulic fluid consistency. Keep in mind the only hydraulic fluid I am familiar with is the type I fill in the scissor lift.
I removed the microswitches. Then realized I did not know how to test them. I assume that the meter needs to be at both end of the electrical contacts and the dash switch pressed. This was moot anyway since I am the only one home except for my young sons.

If anyone can give me specific instructions on testing the microswitches, I would greatly appreciate it. My wife is home tomorrow so if two people are required-it can be done.

So the good news. I thought about cleaning the microswitches with contact cleaner and then realized I stored them at work for the winter. Michigan winters can make aerosol cans worthless. I reinstalled the microswitches firmly. Pressed the dash switch and presto! The spoiler rose.

The down side is I pressed the down switch and nothing. The spoiler error with down arrow came on. First warning light for this issue. I pulled microswitches and reinstalled. Tried again-nothing. Just the error message. Nevertheless, I am happy that there is progress being made. Thanks to everyone for there help.

My thoughts now is that I should focus on the microswitches first. If they can be rules out, I will check/refill the rams. Am I correct in that the Lucas stop leak is okay to use or should I get something else

I measured the height of the spoiler at 8 cm at the middle of the deck. I am also thinking that unless there is a lockout, low hydraulic fluid would cause the spoiler to lower over time.

Thanks again for all the help. Hopefully as I learn more about these cars I can become a contributor and instead of someone just asking for help.

"02996ttx50

i dunno, michael, i would't move to the switches until you've made certain the fluid levels are even, and not low. only because the low fluid level is ( in my limited experience ) the primary cause of intermittent deployment, as well as uneven level. eliminate that, then the switch..

lucas is ok, but on balance.. it won't hurt you to have a can of pentosin chf11s around since that's your clutch/ps pump fill. iirc we mixed a little stop leak, but i'm not sure of it's viscosity vs the pentosin. why not be safe and use the oem fill. i wish i could help more re the switches, but that has never been my issue, or anyone's that i've encountered. always a low fluid level, though the cheap microswitch failure certainly happens. once you re-bleed the system, if that doesn't fix it, then the switches would by my next guess. the pump seems to work? so, that covers all bases since fuse is also working. also, i NEVER mess with the dash switch for manual deployment, but that is largely superstition. i'm happy to let it go up/down when it wants... and NEVER leave it deployed "up" while parked. definitely doesn't like that.

add:... ain;t nothin wrong with asking for help. we all do.

ChemMan

Been a few months since I messed with the wing but I am back to it now. I went through the system. Checked the relays next to the ECU, filled fluid in the rams. I know at least one of the microswitches are bad.

My plan is to replace the microswitches at this point. It looks like either the switches can be replaced or the entire wiring harness for the rear spoiler.

So, my question is: Has anyone replaced just the microswitches? If so, is it a simple splice in of the switches?

I am not sure where all the connections are for the entire harness. Might be easier to do, if, all the connection points are easily accessible. After the summer of digging into the engine bay and laying under the car, I am not too anxious to get too deep in there again.