Here I am

Loss of ODB2 Port network connection, I think it's a TIPM problem

Attention: TDR Forum Junkies
To the point: Click this link and check out the Front Page News story(ies) where we are tracking the introduction of the 2025 Ram HD trucks.

Thanks, TDR Staff

Coolant pressure test kit recommendations

Thinking of selling, anyone else sell/trade a high-mileage 05?

Status
Not open for further replies.
Oh man, that feels so bad.
As an idea, did you try to run it with other CAN Moduls disconnected to check if one of these is pulling the BUS down?
I mean aside from TIPM and ECM that are needed to run the engine at all.

Well, on my truck the only other one there with the ECU is the ABS. It appears to be working without issue. It really doesn't make sense the more I try to solve the puzzle. the tool says can't communicate, but all the other computers seem to have communication with the ECU, as I have no DTCs about a loss of communication with the ECU, and only one time did the cruse control stop working, normally it works even when the ECU is supposedly non-responsive, but it is the ECU that does cruise control, and it is via the network, I can't imagine the steering wheel controls are a direct wire to the ECU, it would defeat the entire purpose of have a CAN in the first place.

I keep coming back to TIPM, but even that doesn't fit completely, the wiTECH talks to every other computer, just not the ECU/PCM.

Now some kind of noise or interference.. but then why are other computers not having problems with the connection to ECU? Just the scan tool or anything via the DLC/OBD2 connector.. which goes straight to the TIPM, and yet there is communication to everything, except the ECU.. makes it seem like an ECU issue, but now 2 different ECUs, and 2 different TiPMS? Nothing makes sense.
 
OK, so digging into wiring diagrams.. the cruise switches on the steering wheel go via a module then directly to the ECU, not via CAN bus.. so when the cruise was not working that might have been a separate issue from the loss of CAN for the ECU at the DLC.. the more I look, the more crazy this thing is.
 
Brainstorming a little.....

I still think you have a noise at the BUS, and every other Component can life with the noise, accepts it. Except for the ECM that says, no, to much noise here, I'm out.

Possible?
 
It could be the ECM is trying to communicate in single wire mode. If you want to test that out, disconnect or cut one of the bus wires at a time to the ECM and see if it duplicates the symptoms. If that is happening you should be able to see it on the lab scope when the problem is happening, but if you can't catch it, cutting the wire should duplicate it..
 
What is "single wire mode" ??

Is it some sort of default mode??

How is it set and/or reset in the ECM??
The BUS is two wire twisted pair. There are fault tolerant and non fault tolerant BUS systems. If one leg goes down a fault tolerant BUS can still partially communicate, non fault tolerant will be dead.
 
Brainstorming a little.....

I still think you have a noise at the BUS, and every other Component can life with the noise, accepts it. Except for the ECM that says, no, to much noise here, I'm out.

Possible?

That was previously my thinking. I did see signals that seemed a bit noisy, when compared to my 2018 Cruze at least. I'd have to compare to another similar vehicle to have a better comparison. That said, in prior troubleshooting, I did disconnect, live, the various computers. That set DTCs right away.. ECU and TIPM saying can not see ABS, and with ECU, TIPM, ABS and others saying can't see ECU.. So, if the ECU was really shut off the entire network, there should be DTCs saying as much, but I get nothing, and there appears to be communication. The only place that can not apparently connect and communicate to the ECU is the DLC connector with scan tool.. which goes via the TIPM, making it again suspect. The only thing I can think of that lets the ABS, TIPM, ABS and other modules continue to communicate with the ECU, but NOT the DLC connected scan tools, which seems it would have to be the TIPM.. because that is the gateway for the entire system.. but to have TWO in a row bad with the exact same problem.. and one that I can find no one else reporting? Anyone running a programmer like a Smarty touch, edge or others that provides display data from the ECU via the DLC would have been seeing this issue as well if it was common, yet I can not find any reports from anyone on this particular issue.. I appear to have a unique issue.

Now, if the wiring was a problem it would affect all the modules in communication, and I would expect some DTCs, the only odd one I have seen multiple times is the U0141, and it is always a stored code, and it comes in after the ECU stopped talking to the DLC and scan tool, but that code says WCM not talking to the TIPM. That is also on the B CAN bus, not the C which is where the ECU is connected. Again, that points back to TIPM, right where all this began!

Now I did notice something odd, my WCM shows as "development" on the ECU details report, Im pretty sure it should say "production". Is it possible the WCM is causing an issue? That seems very far fetched, it's on the B CAN bus and connected to the ECU only via the TIPM that ties the networks together.
 
Digging into that U0141 code in the WCM.. there is not mention of that code for the WCM in the Mopar database!

U0141 No line for WCM to have this Code.JPG
 
What year is your truck again....is htis the 2009?

The reason I ask is that the IPM is a silver box attached to the PDC (power distribution center aka fuse box) on 2003 to 2005 trucks.
If you look clsoely at the lable on the IPM, it is called a totally integrated power module but in fact is NOT AT ALL the same as the TIPM on 2006 and up trucks. Think of it as the first baby step towards the TIPM.

That said, IIRC, the IPM is susceptible to internal corrosion which can affect its operation.

Of course all of this info only matters if your problems are with a 2003 to 2005 truck, not the 2009 listed in your sig,
 
What year is your truck again....is htis the 2009?

The reason I ask is that the IPM is a silver box attached to the PDC (power distribution center aka fuse box) on 2003 to 2005 trucks.
If you look clsoely at the lable on the IPM, it is called a totally integrated power module but in fact is NOT AT ALL the same as the TIPM on 2006 and up trucks. Think of it as the first baby step towards the TIPM.

That said, IIRC, the IPM is susceptible to internal corrosion which can affect its operation.

Of course all of this info only matters if your problems are with a 2003 to 2005 truck, not the 2009 listed in your sig,

It is a 2009, and I already replaced the TIPM as it seemed to be most likely to be the issue. I'm now wondering if it is possible the WCM/SKREEM is the issue? Seems bizarre, but everything about this has been bizarre. The U0141 code in the WCM has been a stored code following a loss of ECU communications on several scans, and no other codes, most of the time. There have been randoms ECU codes that don't exist on this vehicle. Going all the way back to almost new, even the implausible one in the record I added to a prior post. How any U code that is automatic transmission related pops up on a manual transmission vehicle is a true mystery indeed!
 
How expensive would a switch of the WCW be?
Like you say it's anyway suspicious because of the "development" vs "production"issue.

I found the WCM (AKA SKREEM) module, the original part number was superceded by a different part number, usually a sign the orignal number had some problems, thus the newer version. The original was P/N 05026221AO, the current number is 05026221AQ. I found it on Moparoverstock.com for $220 plus shipping cost, but Summit Racing had it for $223 with free shipping.. decided to go ahead and order it, replacement doesn't look too difficult, probably the biggest hassle will be re-programming the keys, but the tool I have should be able to get that done.
 
Does your subscription include TechConnect and Service Library? If so it's there. I can walk you through it if you have access.

Yes, I have the TechConnect, for a few more days on this subscription period. I used the "search feature" it brought up some articles about U0141, but not for it being set by the WCM.. I did however find it in the service manual (I also have that disk). In the service manual, it links over to the page for the code in the TIPM. I printed that one out, but I never see it as a active code, so it then refers to the non-DTC troubleshooting that looks at CAN bus continuity.

Any idea why my WCM is reporting as "development" and not "production"? That seems quite strange.

Looking back at history, I looked at the first sign of trouble, the U1421. The Dealer service record I posted earlier said this was not plausible since it applied for an automatic tranmission truck.. I'm not so sure that was correct. I never dug into it at the time... but looking up that code I see NOTHING that implies it's limited to the type of transmission.... but it does appear it IS something that might be set by an issue with the WCM.. but I'm still digging into that one.

My computer with the software for TechConnect is doing an update and re-start.. when it's done I'll look into it further.

Thanks for the offer to help, really appreciate any help I can get with this crazy situation.
 
So, that MIL that started it all.. U1421, despite what the service record says, I see NOTHING that says that is a code specific to an AUTOMATIC truck. What I see is this: U1421 IMPLAUSIBLE IGNITION KEY OFF TIME RECEIVED. That sure seems like it could be a WCM problem, as the key on and off signal, I'm pretty sure at least, are from the WCM.

Is it possible that has been the issue all along? Could the WCM be causing problems on the CAN B bus that cause the TIPM to interrupt the path from the ECU to the DLC connector? Still seems pretty far fetched to say the least. But, I will find out when I get that new WCM, which won't be until sometime next month..
 
OK, I have the service manual back up again, and going through it again looking closer at that U0141 that showed up multiple times in the WCM... For a stored code, it has you do basically look for CAN signal path in a non-specific way.. but for an active code it has you replacing the module that generated the code, in this case that code only appeared in the WCM. That bolsters my decision to replace it.

I also went down the non-responsive ECU thread, and it does not seem to fit the specific problems, it looks at signal path on the CAN C to TIPM, and power. Well if I had ECU power issues.... I'm quite sure I'd KNOW about it, and if the ECU to TIPM connection was a problem, the ABS would have the DTC for losing comms with the ECU, but that is not showing.. the issue is between the TIPM and DLC (Scan tool).

Also, the TIPM has a DTC for losing comms with the WCM, I have NOT seen that, only the WCM saying it can't see the TIPM.. and of course the odd "development" status of the WCM.

Sea Story time: Back in 1997 I bought my first new pick-up, a Dodge 1/2 ton work truck with the 3.9l V6, 5-Speed Manual. I liked that truck, up until about 14K miles when the gremlins came out. One day it completely went dead while driving at full highway speed just before a large cable stay bridge.. every single warning light possible came on the dash! I shut it down and pulled over with no power brakes or steering. Looked over everything, could not find any issues.. and tried a restart. Starts right up, no like nothing every happened! A bit spooked, I was reluctant to face possible breakdown on that long high bridge.. but took a chance.. for the remainder of that trip it was fine, then did it again later on a shorter trip, forcing me to pull into a drive under momentum.. same thing, shut down, restart.. all seemed fine.

Needless to say, a certain reliability problem, and under warranty. Took to dealership, where the proceeded to check things over and could not find a problem, but said they tightened the battery cable, maybe it was loose (not a chance, but nice try). Only a few days later it gave up for good, the ECU died completely. They towed it in. This is where it gets interesting. In the process of ordering a new ECU, they discover the one from the factory was incorrect, you see in that MY Chrysler had the 3.9L V6, and a 4.0L straight 6, seems it had the wrong one. I'm amazed it ever ran, but apparently the computers were not that complicated yet in 1997. Anyhow, that was not all, the also found a bad wire in the engine wiring harness! The fix was a sight to behold. The jumpered around the bad GROUND wire in the harness with a rather heavy 10Ga RED wire, left outside the loom.. and considered that an acceptable repair for a new vehicle! I was not pleased, but it was not just the wire. After the new ECU and harness hack repair, it ran horrible. Gutless and crappy MPG, with near constant pinging under modest engine loads.. something was still not right, then on occasion it would seem to momentarily cut out when driving.

Long story short, after making a mistake in the supposed non-partial, non-binding arbitration process to get them to take back the lemon they wanted to keep "fixing"... I realized I could not leave my wife while I was deploying with the Navy to deal with a broken vehicle soon out of warranty.. while it was running I traded it for a 1999 Chevrolet 1500. I was so ticked off at Chrysler I thought I'd never buy from them again... and yet in 2009 I did, because I later had a 2007 GMC truck that was also a LEMON (that time I used the clear law, and a lawyer to force GM to buy it back), and in 2009 you could only get a Diesel manual transmission truck from Dodge, or Ford, and it was clear with minimal looking that the 3 year run on that 6.4L was not going to yield a good engine to keep long term, and it had poor low end torque, as well as the manual a theoretical option, no dealership actually had one.. so I ended up with the Dodge, and frankly because of the Cummins engine and manual transmission.

And here I am today, dealing with electrical gremlins again on a Dodge pick-up... Talk about ironic!
 
Ok, found it. The U1421 code is listed in the section the TCM for the AS68RC Transmission.. and it makes zero sense that code could even appear on the list for a truck that does not have that computer, or transmission. Unfortunately I have no way to know which module generated that erroneous code.. But it is an ignition timing related, and the fault says it can be caused by the TIPM, CCN or the TCM (assuming one existed.. perhaps I need to look around, maybe I have a TCM stuffed in there somewhere and never knew it.. given my sea story with my first Dodge, anything is possible!)

Looking at the flow on U1421.. the CCN is suspect.. But I don’t have any DTCs from it, so I’m thinking the WCM is still more likely the issue at this point. Nothing, I mean nothing would surprise me at this point.. I may end of having to replace every computer in the vehicle at some point, I’ve already done the 2 big ones…

I also pulled my scan files going back to 2017, no less than 4 times U0141 appears in the WCM as a stored fault. I had a few other weird ones, I think my favorite being the C2300 Code, not even a listed possible code for the truck! That said, it was mostly AutoEnginuity scans.. and it appears it can glitch, one scan on my 2015 Cruze with that tool gave me a 17 page list of codes, which appeared to be every possible code that car could generate.. but it was a bogus scan, for some unknown reason. It really only had 3 codes stored.
 
Status
Not open for further replies.
Back
Top