Sunday, September 19, 2021
Sunday, September 19, 2021

Good news! DEF head alternatives are coming

By Russ and Tiña De Maris
RVers are in our headlines – getting the credit for some potential solutions to the DEF head problem. If you’ve been following this story, you know that federally mandated DEF (diesel exhaust fluid) monitoring systems have been stranding RVers. It’s a problem with plenty of dynamics, including why the sensors are failing to start with, coupled with a shortage of microchips, and rounding out with recalcitrant industry and government officials. In any event, we have stacks of email from upset RVers who cannot or are afraid to use their rigs because of the issue. But thanks to persistent and innovative RVers, two DEF head alternatives are on the horizon.

Your pressure causes industry and government to act

For weeks we’ve been urging RVers to contact Cummins Inc., the company that has direction over the software that controls the ECMs (engine control modules) that have shut down scores of motorhomes and trucks. When the control module gets a signal that there’s something wrong with the DEF system, it triggers a sequence essentially leading to the shutdown of the engine. In most instances, there’s nothing wrong with the DEF system, it’s just the sensors. RVers have been pleading with Cummins to negotiate with the EPA (Environmental Protection Agency) to allow a software change that would allow affected vehicles to continue to operate if their DEF head signals trouble with the system.

Later, we suggested the campaign for relief include EPA officials, in addition to Cummins. It looks like all your cries of despair may have been heard. Here’s a quote from Cummins: “As we have shared we have been working closely with OEM and industry partners, and the regulatory agencies to find a solution that addresses the widespread shortage of replacement parts related to the DEF sensor failure. We have developed a software calibration for customers who have experienced this failure that will allow customers to continue (or resume) operating their vehicle. Pending the outcome of discussions with regulatory agencies, we expect to begin introducing this calibration across several model years in the next few weeks. The details are being finalized and once ready, customers will receive communication about when and where they can receive the software calibration and next steps once replacement parts become available.”

Devil in the details

The Cummins statement came out Thursday, August 26. It’s a DEF head alternative that may offer relief for many RVers who are broken down with a bum DEF head. But the devil is in the details. For those of you who have not actually “experienced this failure,” but have held back from heading out on the road for fear the “failure” might occur, your relief isn’t so brilliant. If we read the statement literally, if your DEF head hasn’t gone “gunnybag,” you’ll have to wait for it to happen. And if that happens on the road, far from a Cummins authorized shop, well, you can see the problems that could come up.

But hang on, there’s yet another DEF head alternative, and one that may sound better. Once again, we can credit RVers for a solution that industry hasn’t come up with. Mark S. is a smart guy who got into the RV lifestyle when he bought his first rig, a Newmar diesel motorhome. Mark is deeply immersed in all things tech, and shortly after he got his coach, started making a host of modifications to the thing, and now can “voice command” a whole lot of things the rest of us mortals would have to get up and push a button to do.

RVers solve problem that industry couldn’t

Mark and his motorhome found themselves on a two-month trip. In Florida, Mark, like loads of other RVers, got that dreaded DEF check engine light. Happily, a dealer was able to replace his DEF head in short order, but the whole experience left Mark with a bit of anxiety – what if it happened again? He had an 8,000-mile journey planned, and having the DEF head give up the ghost again could leave him in a bad spot. A bit of Internet research soon revealed the scope of the problem of bad DEF heads – and it yielded some other RVers interested in solving the problem – even if industry couldn’t.

Soon Mark and others of interest formed a development group, bent on coming up with a DEF head alternative. It didn’t take them long. With two DEF heads in hand, one that was working, the other that had failed, they were able to determine just what a working DEF head does. Essentially, the DEF head monitors the DEF system. The DEF head communicates the quality (or concentration of urea) of the fluid is within spec. It relates that there is, in fact, DEF in the tank (quantity). This part also reports the temperature of the DEF is in a safe range. As long as the engine control module “hears” from the DEF head that all these parameters are in range, all is good. If not, the ECM (engine control module) is programmed to start the dreaded de-rating process, which leads to an eventual maximum speed of 5 miles per hour.

Tell it what it wants to hear

So what would happen, wondered Mark’s team, if they could construct a device that took the place of the DEF head, and simply told the engine control module “what it wanted to hear”? You might think this would allow folks to cheat and not use DEF at all. But no, other sensors in the exhaust system are also on the lookout for pollutants. If the DEF system were really NOT working – for whatever reason – these other sensors would report to the ECM of the existence of excess pollutants. The ECM would then flash a warning and would eventually shut down the engine.

Prototype DEF sensor emulator in test.

Could the team build a DEF head alternative this way? Indeed. Writing a bit of computer code and feeding it to an Arduino programmable circuit board, they soon had the answer. Call it a DEF sensor emulator. In practice, the DEF head connector that leads off to the ECM is disconnected, and the emulator is plugged into the wiring. The ECM recognizes the emulator as a “DEF head,” and the board simply feeds data. Initially it tells the ECM that the DEF tank is 75% full, the fluid is 70 degrees, and the urea concentration is 32.5%. As the engine warms up, the emulator tells the ECM that the temperature is increasing, and reports an incremental decrease of the amount of fluid in the DEF tank.

Does it work? Is it legal?

Does it work? Already three motorhomes have been equipped with the new DEF sensor emulator and in test runs have showed no problems. The development team will be installing the system in a motorhome that is already sidelined with a truly bad DEF head, and the rig will then be taken to a service center for replacement with a new DEF head.

Is it legal? The federal government takes a dim view, and applies nasty penalties on those who are caught defeating emission control systems. However, the team tells us that the federal regulations do have allowance for taking an “action” for “the purpose of repair or replacement.” How’s that?

Consider installing this new DEF sensor emulator as an action you take. An action that enables your vehicle to continue to operate until you can repair or replace the bad DEF sensor. The regulation reads, “No action with respect to any device or element of design referred to in paragraph (3) shall be treated as a prohibited act under that paragraph if (i) the action is for the purpose of repair or replacement of the device or element, or is a necessary and temporary procedure to repair or replace any other item and the device or element is replaced upon completion of the procedure, and (ii) such action thereafter results in the proper functioning of the device or element referred to in paragraph (3).”

The emulator doesn’t bypass the actual emission control functions of the DEF system. The DEF system continues to pump fluid into the exhaust stream to reduce nitrogen oxides as the law requires. Those facts make the team feel this is a lawful install. As soon as DEF heads become available, users should get them and remove the DEF sensor emulator.

What’s best for you?

Why not just wait until Cummins and the EPA release what appears to be a software patch? That might be just the ticket for some users. Of course, if your rig is presently non-operational, you’re simply dead-in-the-water until the “fix” comes. The problem is for rigs still running without a DEF warning light. It would seem they might have to keep running until they break. Wherever that might be.

The actual cause of the DEF sensor failures isn’t yet known, although it seems it is somehow heat related. Even with a new DEF head installed, you’re still open to an unwanted breakdown. If you have a DEF sensor emulator in your rig and that warning light goes on, it’s a simple DEF head alternative. Pull over, unplug your DEF head, plug in the emulator, restart your engine a few times, and go. The multiple restarts clear the fault codes from the ECM. Now, go get a new sensor (when available) or go have the dealer “flash” your software.

How can I get one?

If you’re thinking you’d like to have a DEF sensor emulator of you own, you’re asking: “How much?” For a few RVers who are technically adept, you can probably do it yourself for less than $100. You’d need the board and the software code. You’ll also need to build the appropriate wiring to plug into your rig’s wiring harness.

But Mark’s development team has a worry. They fear the skills needed to build and program the system won’t be something the average RVer has at hand. When the group embarked on the project, their thoughts were simply to come up with a DEF head alternative. Finding the solution, then writing code, and putting together the hardware was what lit their lamps. They had no interest in becoming some sort of marketing group. That’s where we sit today. The group is working on this issue, trying to figure out if they can simplify the system enough that the average RVer could put one together, or to provide some other feasible alternative. We’ll be staying in touch with them and keep you up to date.

Related

RVers stranded with bad DEF sensors. What does this mean? Are you affected?
Still stuck with DEF sensor issues? Email Cummins and the EPA
Will a DEF head problem ruin your trip?
Opening image: powder extreme on turbodieselregister.com

*****

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##RVT1015b

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EL Laws
15 days ago

Wish there were something like this for a Ford Powerstroke — we wound up having to delete, which we did NOT want to do. I’d like to do my part to reduce emissions, but at the cost of more than $1k to repair the DEF system vs deleting…well, our wallets just couldn’t take that hit. I wince when I see black smoke belching out of our tailpipe if we hit the accelerator too hard.

Trent
18 days ago

My 2016 Ram 2500 truck de-rated on me 3 days ago. Still trying to get towed to a dealer. I was out of town and made it home with 2 miles to spare.

Scott
20 days ago

Or you can pull the negative battery cables, (assume there are 2) give it 15 minutes hook them back up and you should be good to go.

Keith B
19 days ago
Reply to  Scott

Yeah. Why don’t you try that on. Cummins ISX and let us know what happened. We’ll wait here.

Bob
20 days ago

I do not understand, many state DOT have addressed this issue years ago, and most regulate licensing by weight, not length. Of course, only votes “for”this own shorter rigs, votes “against” have larger rigs. Your survey is tainted. My state requires CDL license at 28,500 lbs, no length listed. Also, they use the unloaded weight, because loaded weight is speculative.

Dick Hime
20 days ago

There’s another advantage of towing with a 16-year old Duramax – no DEF. Old tech rules.

Susan J Lundquist
20 days ago
Reply to  Dick Hime

Good answer! Where is that smiley face emoji… yep, 1999 CAT in our 2000 Class A.

Jeff Cantwell
20 days ago

I would be very interested in details on what data the emulator provides. I’ve been thinking along these same lines as I’ve followed this subject I am a Mechanical Engineer and my two boys are software and computer experts. We have the knowhow but I haven’t taken the step of taking my RV apart to determine what’s on the wires. I’m glad someone is doing this.

EL Laws
15 days ago
Reply to  Jeff Cantwell

Keep us posted! Would your research include Fords, which don’t use the Cummins engine?

Dave H
20 days ago

How do I get the parts list and code? I’ll make my own using an Arduino IDE editor.

Keith B
19 days ago
Reply to  Dave H

Stay tuned. Details surrounding exactly what the best way to make it available and practical for the most users are being decided now.

Dave H
19 days ago
Reply to  Keith B

Thank you! I’ve been immersing myself into Arduino. Lots to learn, but pretty fun.

Lil John
20 days ago

To have to go through all this to get a quick “fix” is the reason, after 60 years in the business, I can’t wrap my head around engineer’s thinking. Are you to say that the engineer’s or the Federal Government Pollution folks actually sat down and planned the 5mph thing out? No road safety thoughts? No alternatives? The industry is FULL of these kinds of nonsense. My father had a sign in his truck shop that said it all. “YESTERDAY I COULDN’T SPELL ENGINEER. NOW I ARE ONE!”

Last edited 20 days ago by Lil John
Glenn
20 days ago

Others have already developed and marketed similar products for other vehicles so why not partner with one of them to bring this thing to customers?

Matt Colie
20 days ago

This whole thing reads so much like the early days of the catastrophic converter cars of the mid-70s that it is amazing. (I was employed by an OE at that time.) There was not then actual technology then to have the ECU shut down the vehicle (though the EPA was looking at such a mandate). There were lots of “Catalyst Test Pipes” available to bypass the problem. These did defeat the emissions treatment completely. This is not the same.

It seems at the recommended service is to have the coach towed to a dealer. (Do I need to tell anybody here about the cost and other problems there?) Then wait for non-existent parts to arrive. This is not even really even an emissions problem. That is still all working as it should. It is the equivalent to having your vehicle shutdown because the fuel level gauge has gone bad.

This current problem is enough to keep me from recommending any vehicle with the issue until it is truly cleared.

Gary
20 days ago
Reply to  Matt Colie

Lol. I put a “test pipe on my 78 Corvette. Disconnected the air pump and opened up the fuel nozzle restrictor. I ran great on leaded gas…

Denise
20 days ago

I am wondering if this is having an affect on the trucking industry?

saddlesore
19 days ago
Reply to  Denise

Yes it has.. Many carriers have resorted to having agreements with “power only” companies to repower a load/or supply a power unit to keep the freight moving..

Billyooo
20 days ago

How about some mechanism that for a failing unit, the vehicle continues to operate but the price of fuel increases 10 cents a gallon for the next fill up, then 20 cents, then 30 cents and so on until the unit is fixed. (Sorry, I’ve got great suggestions but no idea how to implement them. Let me pop a beer and tell you about my time machine…)

Glenn
20 days ago
Reply to  Billyooo

Um, how about NO on that one. How about the US government get out of regulating everything I do.

David Telenko
20 days ago

How about screw Cummins & their NO PARTS available deal with the DEF heads. Hey they have a problem with them & replacing the failed parts is at best a temporary fix! What needs to happen is redesign of the unit so it doesn’t fail! OK thats called a RECALL & if not that then a CLASS ACTION SUITE will sure get their attention. Hey I’m one of those guys who’s planing a 3500 mile trip & I’m freaking worried about my DEF system & i shouldn’t have to be. Anyone a Lawyer that want to take them on. Hey i don’t even want a fix it board that only puts off getting a fix, thats going to fail again.
Snoopy

Ralph
20 days ago
Reply to  David Telenko

Cummins does not supply the DEF heads. The vehicle manufacturer does.

David Telenko
20 days ago
Reply to  Ralph

Sorry according to Freightliner, they only provide the DEF tank & Cummins supply’s the DEF head & ADT!
From Freightliner:
In the case of your coach FCCC provides the def tank assembly, it is not a Cummins part. Cummins supplies the Def pump and ATD. 
Snoopy

Keith B
20 days ago
Reply to  David Telenko

The “DEF tank ASSEMBLY” IS the tank and the def sensor head. The issue being discussed here has absolutely nothing to do with the DEF pump, doser or injector.

Paul Smith
20 days ago
Reply to  David Telenko

Your comments demonstrate a lack of basic understanding of how Class Action works and how it would affect us. Let me enumerate. 1) Class Action litigation is all about lawyers making money, not plaintiffs 2) criminal cases come before civil cases in Federal Courts. With Covid slowing the courts down this will be a long long time before producing a result. 3) Even if you won a class action the court mandated remedy would be to compel the manufacturer to redesign the sensor and then it would have to be installed. Including the appellate process my best guess this would be sometime in 2029. Im not willing to wait that long. 4) Class Actions typically settle ONLY when the class action bar has made enough money and not a moment before. Cummins has a 34 billion dollar valuation. A Class Action of this nature wont even make the headlines in their SEC filings. Class action is the wrong tool for this job. Yes there should be a recall, the design is defective.

David Telenko
20 days ago
Reply to  Paul Smith

Hi Paul, thanks for your information, sounds likes you have some knowledge in this area.
Snoopy

Paul Smith
20 days ago
Reply to  David Telenko

Unfortunately. Between the ECM flash from Cummins and the sensor we at least have a couple of ways to keep moving. Safe travels.

Susan J Lundquist
20 days ago
Reply to  Paul Smith

Well said. The only people who make money in a class action suit are the attorneys and a select group of initial plaintiffs. The rest of us are simply the supporting cases.

Keith B
19 days ago
Reply to  David Telenko

David. Did you read the article? A group of people saw a problem affecting them, but more importantly that affected a lot of complete strangers. Those people spent their own time and money to figure out a way for people to be able to make plans without fearing being stranded for an indeterminate length of time. Those people not only solved the problem but then offered to GIVE THE SOLUTION AWAY to anybody willing to spend 125 bucks for the parts and 2 hours of time to follow the instructions. And what did you do? You immediately jumped on the internet and started bitching because the solution wasn’t what YOU, who didn’t lift a finger to do anything yourself, thought it should have been. You should be ashamed of yourself.

Dave H
18 days ago
Reply to  Keith B

Amen brother!

Steve
20 days ago

RVTravel, do you understand that by validating this article, you are complicit in violating federal law. The authors argument that the ‘mod’ does not violate the law is bologna. This device by-passes the DEF system circuitry with the goal to “fool” the system into thinking the DEF supply is ok. This mod is in the same vein as the EGR “delete” mod and just as illegal!

I don’t disagree with correcting an issue (if there really is an issue) but as I have asked before, please supply facts and data, but to date, nothing. The term “scores of RV’ers” tells me nothing, it’s just used to pull in readers. I have pulled a 5th wheel with a Ford diesel over 100,000 miles, my best friend has over 150,000 miles on Cummins diesels and we both know farmers with thousands hours on Cummins engines in their equipment and none have had issues.

Absolutely, anything that can be done to improve / increase the reliability of engines should be done, but let’s do it correctly, not a work around!

Bob M
20 days ago
Reply to  Steve

Our politicians don’t care about violating federal law. So why should we.

Paul Smith
20 days ago
Reply to  Steve

Hey Russ you are now an accomplice! Two weeks ago you were a domestic terrorist. Movin up in the world!

Steve -whenever someone accuses you of violating a law or relies on regulation to make a point its proper to cite which law, regulation or ordinance they refer. Other than that, it just talk. By the way the EPA tried this on me and I told them the exact same thing. Its a poor excuse for reality.

However, accusing anyone of violating the law without foundation is called Defamation. The first test for defamation is that it not be “groundless”. Since you don’t cite any authority in accusing Russ, my guess is you wouldn’t make it through the first summary judgement motion which is also known as the courthouse door.
For your convenience here is the defamation law that Russ might be able to rely on if he cared. https://www.law.cornell.edu/uscode/text/28/4101

Russ is also a reporter. He is protected by the 1st amendment to the Constitution of the United States of America.

Chris Mead
20 days ago
Reply to  Steve

Steve,

”If there really is an issue?” Are you kidding? I have had the issue. Every trucker I’ve talked to at the stops either has had multiple trucks disabled or knows a friend who has. Your fifth wheel, God bless it, isn’t in the same league. You have to experience the angst of a downed rig or that signal the day you leave on a 4500 mile trip to understand. You are entitled to your opinion of course but being a 5th wheel owner, the rest of it will take it for what it is worth.

Steven Peterson
20 days ago
Reply to  Chris Mead

You’re right I have not, and I know truck drivers who have not had this issue either – so like I have asked several times, show us the numbers!

Don
20 days ago
Reply to  Steve

Tell the many RVers on any of the popular forums (irv2, RVnet) that have a Spartan or Powerglide chassis with a Shaw DEF head that they really don’t have a problem. I am sure they will tell you the FACTS!!! That is if you are really looking for them.

William Semion
20 days ago

Let’s also develop one for Mercedes to take care of the system they use that was developed by Robert Bosch.

Tommy Molnar
20 days ago

“The details are being finalized and once ready, customers will receive communication about when and where they can receive the software calibration and next steps once replacement parts become available.” So, it sounds like we’re still screwed while waiting for the elusive parts to become available.

Keith B
20 days ago
Reply to  Tommy Molnar

No, not screwed. This device allow normal operation of your vehicle even with a failed sensor. You can continue to operate normally as long as it takes to be able to get a replacement sensor. The only difference is it is your responsibility to manually monitor your DEF tank and make sure it has DEF. Just check the DEF level by eye and use a refractometer to check for correct concentration of urea every day you are traveling. You MUST continue to keep DEF in the tank at all times, just as before. This device DOES NOT disable the DEF system. It will continue to use DEF fluid to clean NOx emissions.

Sc00ter
20 days ago
Reply to  Keith B

^This.

Keith B
20 days ago
Reply to  Tommy Molnar

I read your comment again and I believe that you must not have read the second half of the article. I agree Cummins’ “announcement” is pretty weak. The second half though, starting with “RVers solve problem that industry couldn’t…” outlines an actual, practical solution to the very real problem of having your rig shut down and out of service waiting for a part that has an unknown delivery date. In its current form it does require some effort on the owners part but if you follow the instructions carefully it can be done in a couple of hours for just the cost of your time and a few parts. My understanding is that this is not for sale. The software will be available for free download but you do have to assemble the hardware and install the software yourself.

Crowman
20 days ago

To say the average RVer isn’t technically adept is an understatement. Half of us are still trying to figure out why the marshmallow falls off the stick while roasting it over a fire. I would buy one of their units in a heartbeat.

Last edited 20 days ago by Crowman
Drew
20 days ago
Reply to  Crowman

🙂

Paul Smith
20 days ago
Reply to  Crowman

I know the developers are working on something that either an RVer (or at least the RVers grandchild) could put together. They are good guys from a variety of backgrounds. Thanks, now I have to go spend the rest of the day contemplating the existential marshmallow question…….. 🙂

Ron Sifford
20 days ago

Should have bought a Ford.

Keith B
20 days ago
Reply to  Ron Sifford

Which Ford 45 foot long Class A Motorhome should I have bought? I don’t know how I missed all the Ford RV dealerships, do you have a link so I know where to go to trade mine in?

Steve
19 days ago
Reply to  Keith B

Ford RV’s, now that’s a laugh!!

Bob p
20 days ago

Just the picture of the emulator tells me you’ll need someone with an electronic background to assemble it. The average person is not going to be able to assemble all those components. In my 30+ years as an industrial mechanic working alongside electronic technicians I would have trouble doing that. One little drop of solder in the wrong place and it’s over.

Keith B
20 days ago
Reply to  Bob p

No, the physical device in the picture is a pre-built, off the shelf development board call an Arduino. Google for it or search Amazon, they are cheap and plentiful. It is a programmable microcomputer. Other than connecting the 4 wires in the picture to a screw terminal there is no soldering or any other delicate assembly work. All that’s needed is the board from Amazon (about $100) and the connector that plugs into the wiring harness (pre-assembled with wires attached from Amazon it’s about $10). The magic is the program that makes it run. You’ll need a computer (Windows or Mac) with an internet connection and a USB cable to connect to the board. Download The emulator software for free and follow the instructions to install it. Put it on a shelf and keep it until you have a sensor failure. Unplug the bad sensor, plug the unit in where the sensor was plugged, run your engine for 5 minutes to clear the sensor codes and keep on driving until you can get a new sensor.

JCKixter
20 days ago
Reply to  Keith B

Can you provide a link for the emulator software download please. Yes, I have had a DEF head failure and have little confidence that the 8th generation replacement will be any more reliable.

Dave H
18 days ago
Reply to  JCKixter

Here is the link for the software you’ll need to push the code to the Arduino board(s). https://www.arduino.cc/en/software

Select the version for the Operating System you have (Windows, MAC, Linux).

My understanding is that the Development team will provide the open source code to the public along with a parts list and instructions. I bought an Arduino beginners kit and have been going through the tutorials. It’s pretty easy and fun. Here’s the link for that:

https://www.amazon.com/ELEGOO-Project-Tutorial-Controller-Projects/dp/B01D8KOZF4/ref=sr_1_1_sspa?crid=3FF7Q6LVFJ1K&dchild=1&keywords=arduino+starter+kit&qid=1630469223&sprefix=arduin%2Caps%2C239&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEyTURMTlNST0kxRUJWJmVuY3J5cHRlZElkPUEwNDI2Nzc1Mlg5SUJKVjFWVDM2RSZlbmNyeXB0ZWRBZElkPUExMDAxMzc2M1RTT1dKR0NNR05TQiZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

Hope this helps…

Irl Sell
20 days ago

GM and Ford Diesel engines suffer from the same problem. I personally have been stranded when my 2015 Silverado 3500 exhaust system failed, leaving my wife and I and two dogs in the middle of nowhere in the Utah desert. I wish I had a way to override the engine controls in order to get off the interstate shoulder to the next town with a Chevy dealer. I no longer trust the truck and am ambivalent about going on trips now.

Keith B
20 days ago
Reply to  Irl Sell

You have my sympathy but this specific problem and this specific solution only applies to Heavy Duty Trucks and Motorhomes with Cummins engines and 12 gallon or larger DEF tanks.

Randy Goo
20 days ago
Reply to  Keith B

My 2019 super C is on an International MV chassis with a Cummings engine. The DEF tank is 7 gallons. Same problem, so it’s not limited to 12 gallon or larger DEF tanks.

Keith B
20 days ago
Reply to  Randy Goo

Oops. Forgot that some Super C’s have the same system. My mistake.

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