Acc and cms fault

[Cablemandan]

4th trip in our new 19 cornerstone
About the 3rd time the acc faulted
I figured out shutting off ignition and restart reset to norm
However this time had a cms failure too
Then a short time later
Said radar fault clear Debri
Then again short time
the entire dash went blank and came back with a big entegra emblem
Then the dash lit up with various icons lighted up then back to norm digital dash
It has been raining all day and cked the connections when stopped
No Debri on sensor of course, all connections looked good
Getting tired of gassing with my foot!
Any idea or similarities and of course, has anyone figured out how to silence the cms!!

[Gary.Jones]

Dan

I have published several long and involved threads on my problems with ACC and CMS faults on my 2019 Cornerstone. They are published under the title "some things I have learned about my 2019 Cornerstone" and describe my four times into a Spartan shop to have the problem dealt with. I also called Spartan maybe 6-8 times with long discussion with them about the problem. Dan is the fellow I talked to at Spartan CS and he eventually referred it to Hunter at Spartan who has authorized a bunch of work.

The long and short is that 6 or 8 months ago, they had no real idea what was doing it. Call Spartan and talk to Dan and he would probably know as much about it as anyone I know of. Here is the operating hypothesis. The crash of the ACC and CMS is probably due to water gaining entry into your J1939 communication bus (the canbus) which runs from the Wabco RADAR unit on the front of the coach back to the Cummins ECM and Allison Transmission and it is the communication bus that virtually all of the information that is moving back and forth on your coach travels. One repair tech found that the J1939 wiring back near the Allison was stretched too tightly in his estimation and was pulling wires loose from the connection of the J1939 CanBus connector to the Allison, and a second guess was that rain/water was gaining access to the terminating resistor socket of the J1939 canbus which is right beside the RADAR unit. I made a temporary waterproof job on that terminating resistor. I wrapped it carefully in good Scotch 33+ electrical tape, and then cut the thumb off of my wife's kitchen latex gloves, and slipped the severed thumb over the now taped and water proofed terminating resistor next to the RADAR unit and then taped the thumb to the connector and then wire tied the connector to a support piece of steel which keeps the connector oriented vertically so any water that hits it runs right off. One of my threads has pictures of my waterproofing job. Now those are all guesses. You said some of your problems happened in a heavy rain. and that is a well known problem. Actually, there are a bunch of well known problems with this system. Most of us don't drive our coaches in the winter or winter conditions but semis with the same system do a lot, and owners/drivers report tons of problems with snow build-up on the RADAR front surface, or ice build-up on the RADAR unit, and any obstruction to the unit (mud, ice, snow, rain) will knock it out. It made my dash go crazy also. It also produced the speedometer going from 65 to 0 to 65 in a few seconds. Once it get sufficiently "confused" the system will shut itself down because it doesnt want you to depend on it to do anything for you, so it simply commits suicide for a while so you are forced to do all your own driving like back in the old days, before 2019!!!!!!!!!!!!

Now, it can get much worse. My problems got so bad that the coach would shift very hard from gear to gear. Then the Cummins started to de-rate itself and it have very little power climbing hills. Mine was at it worst as we tried to come through DC and back up to Pennsylvania, but had to abandon that trip in Hagerstown, where I had to return for the third time (Hagerstown is home to Emergency Vehicle Services, a Spartan dealer and repair shop (mostly fire engines on Spartan chassis)). Anyhow, it was a real mess, and we were very close to having to call a tow truck and be towed into a repair shop, and the problems kept getting worse until we finally started to develop some hypotheses and try some fixes. Spartan was clueless when this first started to happen. I picked up my coach late May 2018 and the problems started in the fall and continued for all of our 3 month fall trip.

That is the short version of it all. Call Spartan and talk to Dan. They had similar problems with Newmar coaches with the same system in it at the same time I was pulling my hair out trying to figure out what was going on. Spartan said we were the first coaches they had encountered with this array of problems. My guess is that they have encountered many more since last fall.

A real problem is that most of those errors are Wabco errors (the people who make the CMS and ACC systems) and there is a special WABCO computer program which is the only thing that can clear the codes once they are "set". Back in the fall, the software was new enough that virtually no shop either had it, or knew how to use it. Interestingly, several Cummins shops (like Cummins Coach Care) said they were not allowed to put WABCO software on their computers so I had to find a Spartan shop that was not exclusively Cummins. That may be better now. Good luck! It was a major pain in the a** and ruined our entire fall trip... going from repair shop to repair shop. And it drove me nuts until we started to get on top of the problem.

Gary

[Gary.Jones]

If you go to the search box at the top of this page, and enter ENTEGRA: ACC fault and CMS fault J1939 canbus, you will start finding all the material about this problem that is here on this forum.

Gary

[Cablemandan]

Originally Posted by Gary.Jones

If you go to the search box at the top of this page, and enter ENTEGRA: ACC fault and CMS fault J1939 canbus, you will start finding all the material about this problem that is here on this forum.

Gary

Thanks for info
Went through bad rain today all day actually but when do finally back off
Shut off and restarted engine
It went back all good
I definitely believe it is rain orientated
I tried to search your lead but just get all kind of stuff
Am I doing something wrong ?
I’ll reach out to spartan tomorrow as we just got back from la to sc
Agrevated but glad there’s info on this
Thanks again

[Gary.Jones]

Dan

Here is the most informative of the threads about my CMS and ACC problems and the J1939 canbus problems and potential cures.

http://www.irv2.com/forums/f278/acc-...-419663-4.html

If you have the time, start at the beginning and move forward through the series. You will see as we discover different problems and ideas and related performance issues.

Also, a correction, the guy that I have talked to most at Spartan is not Dan.... it is Dave Martens. Dave is great. He is really challenged by problems and stays on top of the issue until there begin to get some solutions. Dave is the man at Spartan. I think his boss is Hunter and he is also well aware of the situation and has become more aware of what is going on as there have been other problems.

Gary

[brobox]

Dan, JMO with these MH's driving in heavy rain....they are not water proof. I have also had a different problem driving in heavy rain. There are too many electronic connection underneath that are not water proof. Mine was the Cummins ECM connection. They are designed to sit up high in a Semi, not mounted low in a MH. Heavy rain, I wait it out or stay parked for the day. But that is just me.

[Gary.Jones]

Dan

The WABCO techs were very sharp on issues that were directly related to their system, but the problem is that they have no real idea of how anyone else has installed their system, or how it is configured on a specific coach. WABCO has been around a long time for other semi-related system.... for example, they are a major player in the braking systems on semi- trailer. I found that a young mechanic at a Freightliner shop (about 22 years old, computer literate, and tech savy) probably had the best idea of what was going on in the first round of problems. He cleared all the codes in the WABCO RADAR system more effectively than the shop that was a WABCO shop because he knew computers and he knew the software from his work with trailer brake control. This Freightliner shop was not a Spartan shop but they were more effective initially than the Spartan shop. Then the Spartan shop got another young guy (probably less than 20 years old) involved at their shop and he was comfortable with computers and software and when I got him to talk to the WABCO customer service people, then the Spartan shop started to make progress.

Now, I am not sure if the next time I encounter a big rain storm, I am going to have big problems again. My system worked fine the whole 1200 miles back from Arizona (but there were no downpours during that trip), but then I took my coach to NIRVC for some other problems after that return trip and went through a very heavy rain downpour in east Texas and the problems came back, but less devastating, and the system was largely useless (it actually turned itself off it was so screwed up) while in the heavy rain, but then straightened out after the rain and maybe a reboot of the 12V and Cummins restart. I have not been in another big rain since that time.... Time will tell.

The terminating resistor next to the RADAR unit on my Cornerstone, was unprotected and exposed to rain and all sorts of problems. In all of this, I got pictures of the Newmar implementation of the WABCO RADAR system and their implementation was much more water-tight than my Entegra implementation. Theirs involved a larger encased multiconductor cable that went right through the side wall of the RADAR unit and through a waterproof plastic connector.... there were no exposed wires or exposed connectors.... the terminating resistor appeared to be inside the RADAR unit. On my coach, it was outside. It would be very interesting to get a look at the 20 Entegra units and see if they have adopted a more water-tight implementation. There is another terminating resistor and socket at the Cummins end of the line and that is my next waterproofing project.

Gary

[Harleydeal]

I also have experienced failures in the rain. I am not convinced that it has to do with water infiltration into wiring connections. If that were the case, simply shutting down and restarting wouldn’t rectify it. I think it is more likely the computer is shutting it down because rain is obscuring the radars view and confusing it. JMO, which can be, and usually is, wrong.

[Gary.Jones]

Bruce

You may be partially right and I am convinced that there is no single reason for problems.

One of the most important realizations that I got out of this came from a WABCO customer tech who told me firmly that the system is designed to shut itself down if it starts to not get data that it thinks that it should be getting, isnt getting data at the rate that it is supposed to be getting, or is getting what it considers the wrong or confusing data, because using the WABCO system means that in some ways, you are depending on it to do part of the coach driving and control that used to be your sole responsibility. I hate that aspect of it, but some owners love that aspect of it.... the latter drivers, in fact, welcome the system to take over part of the responsibility for making some decisions on the coach.... Sooooo, if people are relinquishing some control of their coach to the system, then it is up to the system to make decisions on when it cannot be trusted to continue to make those decisions anymore, and the system does that by shutting itself down. That makes perfect sense to me.... if you can't trust it, then it should not be working at all, and the software is programmed to make that decision, and shut itself down. Think of an automated computer controlled landing system on a commercial airplane that starts not to get some of the data that it needs to land the plane or is getting information that makes no sense to it.... it shuts itself off and sounds an piercing alarm to inform the pilot and copilot that they are now in full control. Now, if it simply shut itself down, fine... it should warn the driver with lots of warning signs so the driver knows he/she is back in control of what is going on. The system does that...

What doesn't make sense is that if it decides to take itself off line, but simultaneously it screws up the Allison shifting pattern and Cummins performance or the whole digital dash communicating meaningful data. My assumption here is that it really doesn't, although all of that happened to me and my coach at the same time .... I believe that the other failures in the system and the decay in all sorts of issues was due, not to the WABCO RADAR failures, but rather, because of communication problems along the J1939 canbus system. That is a guess, but I think that it is probably correct.

Gary

[Harleydeal]

Hey Gary,
I haven’t experienced (or maybe haven’t noticed) the other anomalies that you have regarding Allison/Cummins performance. Only CMS shutdown in heavy rain. It makes perfect sense that CMS should shut down if the data is confusing. Did your waterproofing of the connection resolve any issues?
Bruce

[Gary.Jones]

Had one heavy rain afternoon and the CMS and ACC took itself off line. However, it was far less messy than the ones I had last fall. Again, a hypothesis, but my hypothesis is that that incident was simply the RADAR unit becoming confused by the heavy rain and maybe rain up on the RADAR transmitter unit, rather than a fairly complete failure of the CANBUS system which was what was going on last fall. This last problem cured itself when I rebooted the system and turned the Cummins off and back on again and the weather cleared.

I'll know more when I hit the next really heavy rain downpour.

Gary

[Tom78418]

Since the mounting of the radar head in our coach was corrected, issues with the CMS shutting down even in the worst of rain ended. In heavy rain I do not use cruise control and engine brake is left off. Engine brakes and slick roads is a bad combination. Once in clearer weather I use the Cruise Control and on dry roads I switch the engine brakes back on. As for the issue with the radar, the radar head was mounted in a way that it was positioned at the bottom edge of the plastic window in the gen bay door. Raised to be centered in the window resolved the problems.

Have a look at the position of the radar head. If it is not centered, that could be a considerable factor with the CMS shutting down.

[Gary.Jones]

Thanks for the information Tom. That is important stuff. I will look at that....

Like you, I DO NOT every use either old fashion cruise or the new fangled ACC to control my coach speed, EVER, in a heavy rain, or snow, or sleet condition. You just dont want something else applying diesel or brakes other than your brain and foot in my opinion. A difference between you and me is that I dont keep the coach in Jake Brake on position for exactly the same reasons, plus some additional ones. I have listened to Big Mike from Spartan and PJ from Entegra give talks on recommended driving procedures, and both of them strongly recommend NOT running the jake all the time. Their position is that most RV owners that do that are using their Jake brakes much more than they should... their position is that the jake should be used only for what it was invented for.... and that is additional braking on long downgrades on major mountain passes. That is my policy. The service brakes on our coaches are designed to handle 90% of our braking needs. The place they need additional help is on 5 or 6 mile, 7% grades (or steep short hills also). And additional issue is that having the jake on leads to much more jerky coach behavior as it comes on and off when you want to coast on regular roads.... But that is my experience.

Gary

[Cablemandan]

Hey guys, Again thanks for all the responses.
Wow, just briefed back to beginning of and still need to finish, Im up to mid Jan 19'
Talked with Spartan, they say will respond with failure and blocked radar in heavy rain and its normal. (well they say it is?) I do believe remembering back that that was the situation ea. time. How heavy of a rain is now my ? but will be turning off ACC if starts raining and do some waterproofing of my own as well..
One thing I haven't seen addressed yet so far but not done reviewing all, is when mine faults, so does of course the acc, and sometimes the cms but the cms will reboot itself while going down the road and start functioning when the rain clears but the acc will not until i restart the engine. Has anyone tried turning off the 12v breaker to chassis9 have to get out of coach to do anyways but) or coach 12v store button to reset? Think that wont work though.
Just curious and is anyones acc resetting with out restart engine and ignition reboot?
That is the pain in the buttocks part I think if NORMAL.