Frustrating ABS/PSM issue

Hi All, I have been trying to resolve a ABS/PSM issue for awhile now. My durametric says its the Stop Light Switch code 4340. Normally, I would have to drive 20 miles or so before the warning lights come on. I ordered part 996-613-113-02-M100 from Sunset Porsche. I noticed that this part is different than the one in the car currently and its smaller in size. I had issues installing it as it would not twist into place. I had to file the tabs down a bit but still wouldn't turn. I took it to an Indy and he was able to get into place. He tested the switch with his diagnostic tool and confirmed that it works properly. As soon as I drive, the lights come on instantly and its more obvious now that when I step on the brakes, the lights are triggered with the same code 4340. I put the old unit back and verified that it will not trigger right away and it would take some time before the warning lights come on. What do you guys think my issue is with the new unit? I really don't know where to go from here as that is the only code from the durametric. But it is also weird how the new unit is throwing off the lights faster than the old unit. Any thoughts? Thanks for reading. Eddy

What year is your car? Google is your friend Here one of many on the subject https://rennlist.com/forums/996-foru...ng-lights.html

Sorry, should have mentioned that the car is a 2002 C4s

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Thanks, I read through many of the threads already but couldn't figure out why replacing the stop light switch as indicated by durametric made the situation more pronounced. thanks again.

Are all your brake lights working? I have heard of problems with the ABS/PSM light coming on because of a burned out brake light. I would also check the brake switch part number again. Maybe you didn't get the correct one for your car.

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Read post #4 https://rennlist.com/forums/996-foru...ng-lights.html

First make shure you have the correct switch part number there are multiple part numbers that look alike but function differently. Secondly when the brake pedal is not depressed the abs module checks continuity of the circuit. If you have installed led bulbs or the incorrect wattage incandescent bulb, that is your problem

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Yup, I think all lights work. I ll double check again but thanks.

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Yup, got the correct part number as verified by sunset porsch and I don't have any led bulbs. Thanks.

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Yeah, I am working on the right part. I do see the one for the clutch. i think I may try to buy another one to see. Too bad it's a hassle to return the original one to sunset porsche.

I went through a similiar situation as you.Bought a new stop light switch ,still got the abs/psm warning lights coming on and instead of warning lights coming on after driving ,they now came on as soon as I stepped on the brakes.Removed it and returned it ,got another one worked great.Even the dealer parts can be defective .I used a durametric to diagnose this issue also. The second "new" switch fixed it.

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This is exactly what I am going through. Light comes on as soon as I step on the brake after changing the part. I will order a new one and try it out. Thanks so much for your help.

Try pulling the plunger out completely first, and letting the brake pedal find the "bottom". It pulls out with a bit of a ratcheting motion.

Thanks everyone for your feedback. I was able to resolve this issue (fingers crossed) with the new brake light switch. I was about to buy a new one but I recall reading in this forum that someone took the switch apart and flipped the top end facing the other side. I did this and also pushed the metal connectors out a bit. I think this helped and resolved my new brake light switch issue. The ABS PSM warning lights do not come on as soon as I hit the brake lights anymore. Hope this helps someone else out. Thanks again.