GL Mike, hope you have some better news soon. I have a good tech guy in SG if you're interested.

Rich

 

Hello Mike,

Sounds like you and I are in exactly the same boat. I have posted twice on this exact subject and the sad thing is that I'm still in the shop trying to get the problem diagnosed. Here are the two posts...the second one being the latest.
https://www.6speedonline.com/forums/...ht=abs+failure
https://www.6speedonline.com/forums/...ht=abs+failure
Right after I posted my last reply to the "Dealership Doesn't Have a Clue" thread exclaiming my joy that they finally fixed the problem, I had the problem again. Since then this is what has happened...

After the MAF replacements, the O2 sensor replacement, the boost hoses being fixed, they now thought it was a bad DME (ECU). They said they found a shorted wire to the DME so they replaced the DME. Everything check out, computer tests passed, excessive road tests completed (over 40 miles), I am jacked because thank God this ordeal is over. I take it out driving, and ABS/PSM failure lights come on, the idle becomes irregular and the car stalls a few times. The main difference is that I can now duplicate the problem all of the time not occasionally...I start the car, pump the brake, and then the ABS/PSM lights come on. So, I bring the car back in...

That was last week...so far my car has been in the shop for over a week and still no diagnosis of the problem. I told them that the problem HAD to be with the ABS/PSM unit because of the failure lights coming on as well as the being able to duplicate the problem with pumping the brakes. Well, they have another 996 TT on the lot and start swapping out parts to find the problem. They swap out everything short of pulling the wiring to the brakes out and the problem still persists. They swapped a new ABS/PSM unit, still the problem remained. PTech of NA now says to swap out my diverter valves (the only upgrade in the engine) and see what happens. I have to hand it to the foreman at this dealership because he is staying on the job to get this fixed, but I am shocked at how archaic this whole diagnosis progress is. Codes are not accurate, they are just swapping out parts to see what happens, total guess work. They think there is a short somewhere causing these fault codes and failure lights to come on, but that is the latest so far. Sorry such a long post...I will continue to post updates. Hang in there and good luck!

 

I hope they find what is causing your PSM/ABS failure. This might help you.
I got a call from the dealer, they finally found the problem; a broken wire in the ABS wiring harness at the front left wheel. Now they must call my after market warranty company to see if they will cover it. I hope they cover this, and the clutch pressure accumalator.

 

Hmm i'm having this problem myself right now. I should have taken my car to Redwood City Porsche butttt i did a stupid mistake...anyways. Would having PS2's in the front and the orginal Bstone tyres in the rear cause the car to throw this light ?

Thanks
Enrique

 

I am still having the problem, but slightly different events are causing it. Before, they lights would not go out, after braking late into a corner and hitting some potholes on a canyon run. Thedealer replaced the wiring harness. Then afte about week, only when I turned my wheel all the way to the left, but lights would go out after turned off the car and turned it back on. Now, the the abs/psm lights go on driving straight, smooth roads while braking (lightly), at about 30mph , but not every time. I turn the car off, then back on, lights still lit, but after about 10 seconds of driving, they go out.

I am beginning to wonder if it is my tires as well. I have 225/40/18 and 295/30/18, on 8.5" and 11.5" wheels. So the sidewalls are stretched more on the back then the front. It wasn't planned to have narrower tires on these wheels, bought the tire just before I bought the wheels.

 

Hmmm I hope it isnt,good luck solving your problem as well- hmm can anyone with PS2's chip in ?

 

Throwing codes is different then having the car react to loss of traction. You shouldn't throw codes for just losing traction...don't think there is a problem with PS2s and S02s front and back. The problem with the ABS/PSM lights are they are a catch all for a number of possible faults. You really need to get the actual codes read to make sense out of it.

 

I need to get a durametric reader, the dealer wasn't helpful. They even stated no codes present, during one of the visits. They checked, but did not replace, the console cluster. I also used a code reader from Autozone, hoping by chance it would pick something up, no luck.

 

Okay guys i have an update..

My dealer said my steering sensor is bad... so they are going to order one and should be here next week. For now it had been ' adjusted' and its working perfect!

 

Glad to hear you got the ABS/PSM issue corrected.

 

*Crossed fingers* The PSM/ABS failure has been fixed. It was originally the ABS/PSM harnesses in the front wheels. But when the dealer replaced the parts they did a bad job on the wiring. This was the reason for the odd behavior of when/what caused the lights to come on afterwards. I actually took it to a different dealer to get the problem resolved, sense the first dealer began 'throwing parts' at it to fix it instead of checking their original work (or hack job)

 

It's the ABS pressure Sensor. Good Luck on finding a part number. I have been on it for a week now no luck......... Porsche place said $3600 ABS Hydraulic pump. I carried it to a place that works on Eurpoean Autos and they are pretty good. This is what they told me.

 

Wow, that's a pretty serious old thread revival!

 

I had this same problem took me 2 years to work it out, turned out to be a poor connection to the MAF just as you plug it in, found out by moving the wires about as they seemed to be bent over at right angles, anyway had it re terminated and no more ABS/PSM lights on start up or when gently cruising down the freeway. I suggest if any one has this problem in the future to check the MAF plug wire termination.