Punko

No, I didn’t replace the pump. The pump had to be removed to access the cap screws that fasten the control module to the pump. I couldn’t find anyone selling just the control module.

No no programming was required.

Thanks.

DrivenHK

I may be getting 2 different parts confused.
The diagnostic manual, step 10 of 4205 states to replace the "PSM control unit" I thought this was the ECU.
Is my understanding correct that, you changed only the circuitry control portion (black housing) of the ABS hydraulic module? Thanks Punko


ABS Hydraulic Pump



PSM Control Unit

Punko

Yes I only changed the black housing in the first picture.

DrivenHK

Thanks for your reply. Trying to reconcile what seems like conflicting points - Step 10 of the diagnostic manual calls for replacing the "PSM Control Unit". 4205 has 2 solutions, replace the left speed sensor or replace the PSM control unit.

If my info is right, the 996.2 5.7 ABS do not have the PSM ECU as a separate ECU but is integrated inside the DME.

Is this a typo in the manual, and they are actually referring to the module contained inside the black housing?

Thanks!

Punko

The instructions refer to the plug on the black box as the psm control module plug.

DrivenHK

Thank you Sir!

Ahsai

I found it quite interesting that damaging the harness could damage the control unit given that the control unit is supposed to be able to detect short to battery "+" or short to ground, etc. You would think for robustness, the control unit should at least tolerate any shorts introduced by the sensor wire harness.

Punko

When I get a chance I plan on opening up the black box...maybe I can see what the specialist said can’t be repaired?

Ahsai

That would be interesting to see and learn.

Yelo996

I have the same issue. I replaced the suspension on a 2004 C4 S 6s. When I got it back from the shop the ABS and PSM lights were on. The technician could not find any issues. I had another shop look at it and they believed that the front left wiring harness had a short. They repaired that, but it did not change the lights. They recommended replacing the ABS module. I purchased a replacement from eBay from a similar 2004 C4S. Connecting it gave the same error suggesting that this was a wiring problem. The technician had a new ABS module in the dealership and said that when that was connected it solved the problem. I had the local ABS shop take a look at the eBay ABS module and confirmed that it was a good module. We’ve now replaced the left wiring harness and run through the steps above to test for shorts. It makes no sense to me that the original ABS module and the eBay ABS module are both showing faults with a new ABS module does not. Is there any programming that we need to do to the eBay ABS module for it to work?A new module is horrendously expensive.

DrivenHK

Exact same story line. About to choose the 2nd hand route also... Sorry to hear about your problems. Would be great to get to the bottom of this.

Did the module part # match the old one? Conflicting info on whether calibration/coding is required on replacement new/old.
Did you ask the dealership tech whether he had to code the new ABS module that resolved the issue?

thnx

Punko

For my situation, no programming was required. Perhaps find another used module?

jumpy chunky

I'm not a service tech, but Porsche tech 3 is and he stated in one of his posts that an ABS from a tip will need to be calibrated using PIWIS to work with a manual tranny. They are interchangeable otherwise.