Interesting situation surfaced yesterday. Was playing around with my (new-to-me) PIWIS 3 from @rnlst_log . Connected to the car to pull simulation data per Mars' YT video so I can load that into the simulation folders in my PIWIS for casual learning. PIWIS recognized the car when I turned the key on and then enumerated all of the installed control units (there are perhaps 8 total control units outside of the PIWIS 2-related ones (which no longer count since the prior owner of my car ditched the PCM 2 for a Kenwood double-din unit with much better features). Following Mar's video, I did a Select-All for all control units and clicked Next (F12). PIWIS asked if I wanted to create a VAL and I selected F12 (Yes) again to create a VAL. The process started and all control units were listed and PIWIS began to interrogate the first CU on the list - the ABS control unit...... and promptly HUNG. Nothing.

To make sure I did not make a mistake, I backed all the way out of the PIWIS and restarted. Unplugged the VCI (VNCI PT3G) and removed the key from the ignition and stated the whole process again. SAME RESULT!

Backed out once more and decided to query all of the control units individually and every control unit responded just fine - except that is for the ABS unit. And throughout this entire process, there are ZERO faults logged and no ABS warning light (steady or flashing) on the dash ( and yes, the ABS light comes on when turning the key on so it's not the dash light!).

Uh oh......

So I took the car for a test drive to make sure ABS was actually working. Found a lightly traveled freeway access road with enough room to get some speed up and hit the brakes hard enough to activate ABS. Sure enough, the pulsing was there telling me that ABS was working.

So I have a dilemma........

1. Is my PIWIS not configured correctly for a much older car (maybe, but Mars did the remote coding on my Panamera for matrix lighting successfully - my PIWIS plugged into my Panamera to which Mars remotely connected and did his magic work)?
2. Is my VCI having trouble talking to the car? Doesn't seem likely since it could talk to every other CU on the car successfully.
3. Is the electronic component of my ABS unit having an issue - maybe.... But if so then it's being pretty selective about what it wants to talk to! Since ABS did activate in my test, at least the unit is communicating with the wheel speed sensors at each corner of the car.

I'm going over to a shop this morning to see if perhaps it's my VCI. We'll try the Actia/Porsche VCI and perhaps one or two others to see if it's a VCI problem. We may try to get one of their testers to connect with and work with my VNCI PT3G VCI as well. That should eliminate any issue with the VCI.

It is possible that I have something not configured correctly in my PIWIS software, and I have a question into Mars about that (it's version 43.500.011 [1.77.7.23296]).

Or the comm module on the ABS unit is headed south for a permanent vacation. If that is the case, I came across these guys ABS Module Repair - Save Time And Money With Our ABS Repairs | UpFix and they list the specific ABS module found in our cars (996-355-955-93). That part has now been superseded to 996-355-955-HX. UpFix does not list that part but they do list the -FX and -GX part numbers, so I'm guessing they can do the HX fix as well. Since my car does not appear to have had any work done on the ABS unit, I suspect I have the -99 unit installed. This looks like a reasonable alternative to trying to source a used ABS module ($1K if you can find one) or a new one ($6K+ at Sunset Parts!!!!). And they only want to comm/electronic component sent to them, not the entire unit - which means I don't have to go through a flush/bleed process - I think. Somebody who knows far more than me can happily correct me on that point!.

So my question is whether anyone has encountered this issue (ABS not talking to the PIWIS) before? If so, what repair options did you pursue?

For reference purposes, my car is a MY 2004. I did upgrade the brakes from the steel 6-piston/4-piston setup to the M450 PCCB option. I used all factory parts (except for the rotors themselves which were reconditioned by Redisc in Slovenia). The is no difference in the ABS Control unit/pump between steel and PCCB setups.

Any input would be greatly appreciated.

Toby

 

I went down this rabbit hole with my abs. It turns out that piwis2 and 3 rarely work as intended in our cars. There may possibly a communication issue but the entire car is 1st gen canbus with out dated firmware so comm errors and freeze screen r common.

I swapped electronic modules in my car with a used abs, eventhough the old one was working fine, and had no change. I can check the SN on my original '04 unit and send it to u for testing purposes if u want.

 

Well, good news.... My shop connected with an Autel scanner and could interrogate my ABS unit just fine. So, no issues with the unit itself.

As for the PIWIS 3, I suspect the culprit is the VNCI PT3G VCI that connects to the car. I'm not sure that even the Porsche/Actia PT3G (either version) would be successful either! I've got a Tabscan T6PT3G on order just to validate.

SMH at the PIWIS software design. A 10 year-old could think more intiutively than could the Bosch programmers who originally came up with the Hammer and the PST2!

 

So it appears that the PIN-OUTS on the VNCI PT3G different from how the OBD-II port is mapped on the GT3. I have some suggestions from Mars to try tomorrow. If they work, I will report back. Also, I have ordered a Tabscan T6PT3G VCI so I can see if it works. If it does without having to make any VCI mapping changes, I'll likely sell the VNCI unit.

Gotta love technology!

Toby