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OTR Diagnostics, DEF, Derate Faults

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ARD

Staff member
RVF Moderator
RVF Supporter
Joined
Nov 2, 2019
Messages
1,136
Location
Fulltiming
RV Year
2022
RV Make
Newmar
RV Model
London Aire 4551
RV Length
45
TOW/TOAD
Yukon Denali
Fulltimer
Yes
So it's been a fun few days (cough). As I was driving up a mountain pass, my check engine light and alarm went off. With nowhere to pull over, I stopped in the slow lane and called Spartan. I had 3 DEF faults and found out later I had a 4th, an engine torque derate fault. As I was 30 miles from the campground, I was advised by Spartan to continue on and call him once I arrived. He told me I needed to find a Cummins authorized person to come out and clear the codes and do a forced regen. He said my DEF faults indicated that the sensors detected some abnormality. He also said that they have very few spare parts and they are reserved for people stuck on the side of the road. FYI, new DEF parts will be available in August, as they are waiting for chips from China.

Jake from Jake's Diesel came out to help me. If you are ever in Pagosa Springs, he is the one to get help from. He helped me two years ago with a slide motor. Reasonably priced and smart as a whip. In any case, he reviewed the faults and my connections and felt certain that a forced regen would take care of it. I followed him to a parking lot that trucks utilize and there we did the forced regen. It indeed worked.

I share this experience for a couple of reasons. There is a post on the other forum by the Newmar Man about disconnecting the speedometer as a temporary/emergency fix to make your destination and not have to be towed. In the thread someone mentioned they tried it and it did not work. I asked Jake about it and he advised against it as he felt it would further compound the problem. As I continued to read about Cummins fault codes, I read about the OTR Diagnostics Tool which can be used to clear codes and do a forced regen. That sounds like a much more reasonable emergency tool to have on hand. Later in the thread, a couple of people also mentioned this tool and carry one. I was curious if anyone here has it and/or used it?

The other reason I'm sharing my experience, I was curious about whether I would get a warning before the red, stop engine light came on or did it just KABOOM come on and you are dead in the street. It pretty much can KABOOM come on; however, there are a couple of warning signs. I had no idea I was just a step away from the red light. So as it was explained to me. Check engine light goes off. 1st warning. Check engine light with check in it. 2nd warning. Next comes the red light. I'm not sure how many more miles you can go before you get it, but you've been warned twice so find safety.

My last outstanding question I have and I will be calling Spartan tomorrow. Is this a temporary fix? Or did the sensors detect something abnormal and the forced regen take care of it? Or do sensors need be replaced.

Oh and just another bit of information. My DEF gauge read that I had a full tank of DEF while this was happening. When I turned off the ignition and restarted the engine at the campground, it went to 1 green bar. That was confusing as I would think if you had one bar, it would be red. I did a visual check and my DEF tank was pretty full. It took on about 3 gallons. I'm not sure what was going on there. I believe it should have read 3 bars instead of 4. Will be keeping a watch on that for sure.

Any and all feedback is welcome. I learn so much through these dialogues.
 
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So it's been a fun few days (cough). As I was driving up a mountain pass, my check engine light and alarm went off. With nowhere to pull over, I stopped in the slow lane and called Spartan. I had 3 DEF faults and found out later I had a 4th, an engine torque derate fault. As I was 30 miles from the campground, I was advised by Spartan to continue on and call him once I arrived. He told me I needed to find a Cummins authorized person to come out and clear the codes and do a forced regen. He said my DEF faults indicated that the sensors detected some abnormality. He also said that they have very few spare parts and they are reserved for people stuck on the side of the road. FYI, new DEF parts will be available in August, as they are waiting for chips from China.

Jake from Jake's Diesel came out to help me. If you are ever in Pagosa Springs, he is the one to get help from. He helped me two years ago with a slide motor. Reasonably priced and smart as a whip. In any case, he reviewed the faults and my connections and felt certain that a forced regen would take care of it. I followed him to a parking lot that trucks utilize and there we did the forced regen. It indeed worked.

I share this experience for a couple of reasons. There is a post on the other forum by the Newmar Man about disconnecting the speedometer as a temporary/emergency fix to make your destination and not have to be towed. In the thread someone mentioned they tried it and it did not work. I asked Jake about it and he advised against it as he felt it would further compound the problem. As I continued to read about Cummins fault codes, I read about the OTR Diagnostics Tool which can be used to clear codes and do a forced regen. That sounds like a much more reasonable emergency tool to have on hand. Later in the thread, a couple of people also mentioned this tool and carry one. I was curious if anyone here has it and/or used it?

The other reason I'm sharing my experience, I was curious about whether I would get a warning before the red, stop engine light came on or did it just KABOOM come on and you are dead in the street. It pretty much can KABOOM come on; however, there are a couple of warning signs. I had no idea I was just a step away from the red light. So as it was explained to me. Check engine light goes off. 1st warning. Check engine light with check in it. 2nd warning. Next comes the red light. I'm not sure how many more miles you can go before you get it, but you've been warned twice so find safety.

My last outstanding question I have and I will be calling Spartan tomorrow. Is this a temporary fix? Or did the sensors detect something abnormal and the forced regen take care of it? Or do sensors need be replaced.

Oh and just another bit of information. My DEF gauge read that I had a full tank of DEF while this was happening. When I turned off the ignition and restarted the engine at the campground, it went to 1 green bar. That was confusing as I would think if you had one bar, it would be red. I did a visual check and my DEF tank was pretty full. It took on about 3 gallons. I'm not sure what was going on there. I believe it should have read 3 bars instead of 4. Will be keeping a watch on that for sure.

Any and all feedback is welcome. I learn so much through these dialogues.
Everything that I just read in this post is almost completely what has just happened to us we had a check engine light come on and then go out it came on again however with no check and then it went out and then an alarm went off that said low DEF we pulled over got out checked it it had a little over half a tank my husband added to the tank 2 gallons we started the engine again the check engine lightIs still on however the DEF bars again say fall and there is no alarm. And we are coming home from Las Vegas national indoor RV service for the second time in a month and a half for an engine light problem they clear the code and say you’re fine call Cummins.
I feel it is a sensor but no one has mentioned this we just changed our DEF filter at NIRVC. I’m sorry it’s happening to you but I do take some solace in knowing that you were also on the problem. Thank you for this post again what a wonderful sight to see us thank you Neal for passing this on.
 
Hi, welcome, have not seen posts before. One freightliner person (you have spartan, may be same) said to turn key on, wait until all the gauges cycle and get to their non running spot, then start coach, 10-15 seconds usually. He said that starting it right off might cause an engine check light. I had that happen once and after that info, never again.
I also was under impression the Emissions system did a "regen" as needed, and think but have not investigated a way to force one. Again, we have freightliner chassis, but Cummins engine.
DEF Tank, never had gauge not read close to correct, but I generally always fill it up when it's down to half or so when traveling. I got the caution level indicator once, and never let that happen again. I personally don't use the truck stop DEF, and alternate between the Walmart brand and the Blue Stuff every other 2.5 gallon jug. I try to keep one almost full one with me if out in the boondocks and DEF is needed.
I think, you might have something going on with your emissions system. Several reports of DEF tank head failure, and there is a filter (supposed to be good for 200K miles), but if you take it in for service, have it changed anyway. Keeping DEF tank full even when sitting is a good idea, because it eliminates crystals forming and blocking up system. DEF has some shelf life issues in very hot weather. Here is a link to DEF video session (2 parts) and will let you know everything you ever wanted to know, and some stuff maybe you don't.

As an aside, if in steep mountain passes, lots of hill pulling, the engine is working harder, and running hotter. Although I think almost impossible, the angle of ascent might be causing the level to shift enough at or below half to cause some issues. I usually fill tank up every evening when traveling, just to be on safe side. Yeah, I know I'm anal.

For jagpot and OP, I believe both have emissions issues, Cummins is my first choice, but if in/near Tolleson, AZ the Velocity Truck Center is excellent, (Freightliner). Cummins Coach Care, Coburg, OR and the one in Portland, OR is also excellent, Coburg 1st choice. I have not used Las Vegas Cummins for work. I believe Cummins is wayyyyy better than any dealer, except for Newmar Factory, which is also excellent. Have had mediocre reports for Spokane, WA and Chehalis, WA Cummins. Chattanooga, TN and Gaffney, SC is also excellent. Let us know.

 
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Thanks so much for your help.
 
We feel your pain as we had a very similar situation while in the middle of a 35 state trip. We actually had to be towed twice before the problem was identified. In our case the whole problem with our engine being throttled down and our DEF level gauge was very inconsistent due to Contaminated DEF. We filled our DEF tank up at the truck stop pump. (Pilot). Freightliner in Lexington KY identified the problem that a possibly a tea spoon or less of diesel fuel got into the DEF tank. We actually had to have our tank removed and power washed and the DEF pump replaced, and the above problems disappeared. This may or may not be your issue but we wanted to share our experience and hopefully your problem gets resolved quickly.
Safe Travels.
 
UPDATE: Sadly, clearing the codes and doing the forced regen did not resolve the matter. It was a temporary fix. I started my coach to get the stored codes and got a check engine alarm with SPN 3031, FMI 9 code. FYI, Spartan said doing a forced regen with this one code would not work. The codes we cleared previously were:

SPN 1761, FMI 9
SPN 3031, FMI 9
SPN 3364, FMI 9

I need a DEF head, but they are only shipping to people who have derated with red light, stop engine and are basically stuck on the side of the road. So, I don't know what's going to happen. Take note that if this happens to you, you do NOT want to turn your ignition on and off. Don't turn on to check codes. Keep engine running while getting fuel. They don't know if engine will derate in 100 miles or 800 miles.
 
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@ARD how long do you have to wait to get a DEF head?
 
@ARD how long do you have to wait to get a DEF head?
They won't send me one. The person I spoke with said it was more likely to be September, October before they get parts. I am hoping they will reconsider since I'm a fulltimer and don't have anywhere to go to just wait til September. I'm thinking it is inevitable that I will be stuck on the side of the road. I received some good advice from @Old-RV'er and starting the search for parts now. ??
 
UPDATE: Sadly, clearing the codes and doing the forced regen did not resolve the matter. I started my coach to get the stored codes and got a check engine alarm with SPN 3031, FMI 9 code. The codes we cleared were:

SPN 1761, FMI 9
SPN 3031, FMI 9
SPN 3364, FMI 9

I need a DEF head, but they are only shipping to people who have derated with red light, stop engine and are basically stuck on the side of the road. So, I don't know what's going to happen. Take note that if this happens to you, you do NOT want to turn your ignition on and off. Don't turn on to check codes. Keep engine running while getting fuel. They don't know if engine will derate in 100 miles or 800 miles.
So sorry for you. Ours has never D rated nor has any check or red light come on just an engine light outlined. We topped off the DEF the low DEF went out the alarm went off but check engine light is still there. I we had it at national indoor RV center in Vegas twice now all they could do is clear the codes. We are not now back in LA and will take it to Cummings.
 
Is this only a Spartan Issue? I have not seen anywhere first hand information that FL has the same problem.

@Dutch Star Don stated elsewhere on the www that spartan and FL use different heads. There is also information that internal components can be replaced individually, and that may resolve the problem.

This whole spartan being caught without parts for the def head is very similar to FL not being able to keep our PDMs running due to supplier issues. So most FLs are running without tail lights or brake lights, and don't even know it.
 

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