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Check engine 1 & low DEF warning

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J&JD

RVF Supporter
Joined
Nov 3, 2019
Messages
2,283
Location
Fremont, California
RV Year
2017
RV Make
Newmar
RV Model
Dutch Star 4018
RV Length
40’
Chassis
Freightliner
Engine
Cummins ISL450
TOW/TOAD
Jeep Wrangler Sahara
Fulltimer
No
Headed from the Bay Area to Oregon this morning and this popped up on the dash. DEF tank is full with 4 green bars showing. Freightliner said it could be no big deal or maybe not & to just have it checked out. Not fun to drive with this on but so far 200 miles with no derate. Anyone else have this show up?
13C64AD1-A8C1-4000-99DE-96C90730470F.jpeg
 
Looks like you need a DEF header replacement. I've had 2 on my 2017 4369F. Never had a derate on either one.
 
Personal experience says there's a stress level waiting to be measured with that damned amber light staring at you. Constantly watching for an escape route for when the light turns red does bad things for the human at the wheel. My only advise is to resolve the situation as soon as possible. Wishing you the best!
 
Mine did that about a year ago...showed about 3/4 tank at the time, but I pulled over and added a box and a half of DEF and it went out. I've never added that much DEF at one time and was never confident with the gauge after that so I took it in to Freightliner...they checked it and replaced the DEF head. I only use the boxed DEF so always have some in the rig.
 
Our view tonight. Threw all the codes for a DEF derate and will be towad 130 miles tomorrow to the nearest Freightliner dealership. We are not happy campers and have no idea how long the coach will be laid up waiting for parts. ???
F160F5D8-9D6D-4851-8CA3-F6EFB3CAFF90.jpeg
 
That really stinks. Let me know if I can be of any help helping you get home if you have to leave it.
 
That really stinks. Let me know if I can be of any help helping you get home if you have to leave it.
So many thanks! We have the jeep to get us home?
 
For ALL-Cummins has released a software patch which fixes this issue, well wrong term. It overwrites the DEF head, and makes engine operate without def. At least that is what I understand it to do. I do not know the details, all outlets are to update system with new patch. Once parts in, repatch and replace the faulty parts. Check with cummins and Freightliner/Sparten for the complete story, check websites might be quicker. Good Luck.
 
For ALL-Cummins has released a software patch which fixes this issue, well wrong term. It overwrites the DEF head, and makes engine operate without def. At least that is what I understand it to do. I do not know the details, all outlets are to update system with new patch. Once parts in, repatch and replace the faulty parts. Check with cummins and Freightliner/Sparten for the complete story, check websites might be quicker. Good Luck.
Only partially true according to a tech we had come to the coach to try to clear the codes (unsuccessfully). He said Cummins has released the bypass codes only for the latest model engines (2021) and they would be slowly releasing them for later model engines in the coming weeks, hopefully. True info? Who knows for sure.
 
Yes, that is the information I think I read. But something is better than nothing. Nothing is having RV sit at repair place for months while parts are sitting on a ship in CA harbor awaiting all the bottlenecks to iron out and for them to be unloaded. So we have choice, wait unitl patch is approved down to our year, or wait possibly 6 months for the bottleneck to clear, clearly, the shorter wait time is better.
 

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