PSM light staying on. - light off, Durametric worked

clicking the button does nothing. A search did not yield much. I was driving last night and as I pulled onto an interstate the light came on. I am not sure when exactly but I turned on the cruise control and used my left indicator just before it turned on. I tried to turn the car on and off a few times and it is still there. no other lights are lit up on the dash. Any ideas?

Go to Autozone and borrow their code reader....see if it will record an error code and go from there. When is the last time you had your brakes checked?

I have an OBD II reader. I can hook it up but the check engine light is not on. I just drove it again today. the light is still on. The brake pads have some life left and they have not tripped the wear sensor yet.

PSM is not emissions based (OBDII). You will need somebody with a PST2 or PIWIS more likely the dealer.

Is your ABS light also on? Could be a steering sensor fault.

nope, ABS light is not on. I will keep an eye out for other lights turning on, some of the reading says that if the PSM light and another light it could be the MAF.

Quotes source post: 5034117

Where did you read that? By the way, what is your car model and year? Which PSM light is on? The ! or the PSM OFF? Do you have an OBC that is displaying any further messages?

Check to see if your brake lights work (you will need a second person). If they don't then you have a bad brake light switch.

Good one Loren. Actually if you do this in your garage with the door down you could see if you brake lights illuminate (or just back up to a window at the front of your house).

Some other things to check: - Fuse E10 - Activate / release the parking brake several times (switch might be sticky there) Otherwise, diagnosis is very involved as there are about 100 pages in the manual devoted to PSM fault identification.

Fuse E10 is still OK. I actually checked all the fuses that had something to do with PSM. they all were fine. The parking brake is functioning properly. (the light goes out when I release it) Brake lights work but I am getting the wife to make sure they ALL work.

2001 986S PSM off is what is lit up. the "!" light is not on. I read it is common on the 996tt for the PSM light and the ABS light to come on with the failure of the MAF. rennteam or 6-speed. I cannot find it now. I have a friend in the Porsche club that has this I will go try it tomorrow night and see what reads out.

PSM is not working. I can spin tire all I want now.

Why in the world would PSM/ABS light up for an emissions based offense? That makes no sense. The reason I asked what lights were on was b/c there are 2 PSM lights and both serve very different purposes. Sounds like your PSM is malfunctioning since it does not engage. This sounds like a definite trip to the dealer or your local indy that has PST2/PIWIS.

As everyone else states, you need to have the ABS/PSM system errors read out by a proper tester (PST/PIWIS/Durametric) According to the factory manual: There are 3 warning lights for the ABS/TC system. 1) The triangle warning lamp is the info lamp for FDR (I assume an acronym for TC), the ASR and ABD systems. If FDR, ASR or ABD function it flashes. 2) The PSM warning lamp which illuminates if: The FDR is faulty ABS is faulty FDR is switched off or the ABD is being activated 3) ABS warning lamp, illuminates with ABS fault The only errors i know of that will deactivate only PSM is low brake fluid level, transverse accel sensor, turn sensor, and certain pressure sensor and booster pump sensor errors. All other errors result in the loss of all the PSM, ABS and TC functions.

Duramatric is what I am going to use tonight. I will post up what it reads out the fault as. so it sounds like I should test to see if ABS is working. The light is not on so I expect it to work. I can check that easy enough! I will check my brake fluid level, but I think a light would be on if that fluid was low. I downloaded the Durametric software to my laptop so I can check the car using his hardware.

I am getting a fault when I check under the ABS 5.7 /PSM tab. 4480 Unknown DTC. It will not let me clear it. when I try to clear fault memory it gives the second picture. also I cannot check the over-revs on the engine or some other stuff the software is supposed to do. Other interesting faults: Alarm Current Fault Codes -------------------------------------------------------------------------------- 25 W lead Status: not present Frequency counter: 1 -------------------------------------------------------------------------------- 33 Interior sensor faulty Status: not present Frequency counter: 5 Airbag Current Fault Codes -------------------------------------------------------------------------------- 3 Supply voltage -------------------------------------------------------------------------------- 1 Airbag warning light Engine stuff: Motronic 7.2 Vehicle Data -------------------------------------------------------------------------------- Porsche part number 98661866005 Supplier part number 0261204790 Software version number: 004157029000 Number of ignitions range 1 17909 / 1781h Number of ignitions range 2 0 / 0h Operating hours counter 1789 VIN: WP0CB29811U665107 Type ID DME control unit _986SUS01 Order type 986320 Country code C02 Engine type 9621 Engine number Transmission type G8620 Transmission number 0 Radio code 0 Body color/convertible top color 6B4A10 Interior equipment MC

It has been a while since I used mine, but the Number of ignitions range 2 is the over rev, yours shows 0.

Based on code 4480, here is some info. May be related to your booster pump or connection. As I said above, it's been a while since I used mine, but I thought you could select the error to bring up more information.

Nice! Thanks DFC! it would not let me select the fault code although it looked like I should be able to. where do you get the PDF's of the fault codes? PET? after hooking the unit in again and trying to reset the PSM fault it worked! I started the car and the light was off. I just got back from a test drive where I tested the PSM and it worked great. I was able to turn it on/off with the button. Everything looks great now, I hope it stays that way!

Great! Hope it's back to normal for good. The info was from the 996 Group 0 Diagnosis Part 1 (up to Repair Group 45) workshop manual. No affiliation, http://www.cannell.co.uk/Manuals.htm

Fault code 4480 Possible cause of fault - Short circuit to ground/B+ or open circuit - Booster pump motor locked up/faulty - Wiring/plug connection faulty Have you checked to see if the fuse is blown? (fuse B9)