Using a PIWIS 3 to diagnose a non-running 996

[Porschenstein]

On the VI/GN wire, should I only check continuity back to the DME or should it have voltage? Thanks.

[JFP in PA]

That photo looks like it was on a trailer; your post made it sound like you flat towed it (on the ground), which would be a major no-no..................particularly if you flat towed it in gear!

[JFP in PA]

36 minutes ago, Porschenstein said:

On the VI/GN wire, should I only check continuity back to the DME or should it have voltage? Thanks.

Should have both, continuity to prove the wire is intact, low AC voltage which is what the CPS generates as it is a simple Hall effect device.

[Porschenstein]

I read a Jake Raby post regarding tractor trailer hauling in gear where they have seen issues with the flywheel.

I thought maybe it rocked back and forth enough to bend a tooth or something.

 

Thanks for the VI/GN test info, I'm thinking I should check it everywhere. Where is the Anti-Skid Regulator located?

[JFP in PA]

Do you mean the ABS system?

[Porschenstein]

48 minutes ago, JFP in PA said:

Do you mean the ABS system?

It's on the same page as ABS, I don't see VI/GN going to ABS, maybe ASR in only on C4? Thanks for helping out.

[JFP in PA]

ASR, which is actually a form of traction control, is part of the ABS system as it uses the brakes to limit wheel spin.

[Porschenstein]

I took it to a prominent Indy in Atl a few days ago, they couldn’t get it going. Their analysis was the wiring harness is too far gone and must be replaced. The CAN bus is very sensitive to resistance and this harnesses was flooded in saltwater for several days or even weeks possibly.

I’m going to try to do a more thorough repair on the harness or replace it.

[JFP in PA]

It would have been immensely helpful to know the car was under salt water from the very beginning.  Realistically, most of the harness is probably toast, along with a lot of the sensor, and in particular, the immobilizer and DME.  Immobilizer failures are common in these cars when they get just a bit of water under the seats due to blocked rain drain holes; immerse it in salt water and you have a paper weight.  Same goes for the DME.

 

At this juncture, you are looking at a very time consuming and rather expensive harness replacement, with same applying to the immobilizer and possibly the DME as well, along with just about every electronic control module in the car.

 

All I can offer at this time is "good luck".

[Porschenstein]

DME is good, immobilizer replaced & coded. PIWIS can talk to both & test / activate the components that it lets you activate. Same with the cluster. It actually seems very close to being happy, I’ll keep working on the harness and see what happens. Quite the challenge but I have time to play with.

[Porschenstein]

In the first post I included the service values report from the PIWIS and also a link to another thread that covers a lot of what has been done. It's not like I came home with it and said "let's see if it runs". I Immediately gutted it and started looking for and repairing damage. All modules are found by the PIWIS and the report shows what was found. The reason I didn't mention that it was flooded is because responses like "it's a paper weight", and "good luck" aren't helpful and a cop out for people who can't handle a serious challenge. Here's the paper weight BTW, are you sure it was bad?...

 

 

 

[JFP in PA]

1 hour ago, Porschenstein said:

 The reason I didn't mention that it was flooded is because responses like "it's a paper weight", and "good luck" aren't helpful and a cop out for people who can't handle a serious challenge. 

 

 

No, it was not a "cop out", and came from someone whose shop has faced multiple submerged cars for customers and insurance adjusters.  The fact that it was under salt water would have changed my entire approach, starting with replacing the harness and possibly several sensors known to be problematic after submersion.  We have seen cars that were in both fresh and salt water, and the latter were always the worst, and often not recoverable in an economically feasible manner, which is why the insurance companies wrote them off.  And of the ones that were salvable, most continued to be plagued with a wide variety of problems related to the immersion for years after they were put back on the road, which is why I said, "Good Luck", and why we regularly caution parties potentially interested in cheap flood cars; they can become black holes for money with little resale value.

[Porschenstein]

Okay, I apologize for the snippy comment, as you can imagine I've had tons of "you're wasting your time" comments so I'm a bit hypersensitive but do appreciate a sincere "Good Luck". I also appreciate your time to assist me so far.  

 

I'm under no delusions that this should have been an easy project, I knew going in it was a massive and crazy endeavor. At the end of the day it's a machine, determine what all is wrong with it and it will run. This is also a huge crash course on the 996, when I'm done I will be intimately familiar with the car. The main reason I sold my last one was due to how expensive it was to have anything done to the car and I wasn't comfortable working on it myself. Thanks again and sorry for being a smart @ss.

 

Edited April 7 by Porschenstein

[Porschenstein]

The X2's were a big ball of green, this is after cleaning up enough to finally get them apart. Before I replace the entire harness I'm going to replace all of the connectors that I had deemed good enough. After discussing how sensitive the CAN bus is with the Indy techs I've decided my good enough was no where near good enough. I repaired broken wires and pins then soaked them in a mild Hydrofluoric acid solution. This did a great job of removing all corrosion but also removed the tin plating. So now the copper is corroding quickly.

[JFP in PA]

No apology is necessary; having been down this road before, we just try to provide whatever benefit that experience can provide; people will always tell you that it is really easy to look like you can walk on water when you know where the rocks are; what they don't tell you is how hard it can be to find those rocks 😉 

[Jay B]

Just wanted to post a "good luck" from over the pond.  I am on a similar journey with a boxer so same wiring as a 996.  Mine had water getting the air filter housing and this had flooded the under seat area.  I had a good DME and the Alarm module reprogrammed by a very helpful specialist.  When I started pulling the car apart I found all sorts of issues with the wiring loom.  Some common circuits had been joined up and they had issues with the 86s circuit.  I lost confidence in the loom, so took it out and replaced it one from a wrecked car.  However, the replacement loom does not have same options and most importantly no Porsche stability control.    I have now learnt that my car has YAW control as part of the Stability control and the ABS pump connector is different.  I am currently thinking about repairing the old loom, as the car has fault codes and the Durametic can not communicate with the DME.  

[Porschenstein]

On 4/9/2024 at 9:43 AM, Jay B said:

Just wanted to post a "good luck" from over the pond

Thanks, same to you. Hopefully now that you have two harnesses you can make one good one. Try to use the minimum amount of solder, I'm told the CAN bus is extremely sensitive to changes in resistance.

[Porschenstein]

Can anyone say with certainty that the Airbag module can or can't be used in a car other than the one it was locked to? I've seen post saying no it's VIN locked and others saying they used one with no problem. I know this can shut the fuel pump down in a wreck, so I'm wondering if it might have my fuel pump shut down because it is not the original one for my car. I will say from what I've seen, it doesn't appear to be a VIN lock, I think it's locked to the model. I looked at all coded values with the PIWIS in engineering mode and didn't see VIN in there. Just for giggles I told it to lock it and it flashed Model 996 right before it said it was already locked. Those two things lead me to believe the lock is on the model not VIN. Also, it is error free, and it automatically found my two new igniters in the door sills.

This guy:
 

Edited April 10 by Porschenstein
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[Porschenstein]

Basic values, ECU Part#, ECU S/N, Unknown Revision maybe, driver side igniter S/N, Pass side igniter S/N. (The igniters are not original either, automatically found)
 

[Porschenstein]

No value for VIN: