Emergency DEF bypass

[Rich W.]

I am going to try to build one of the Bypass units following available instructions above. Looks relatively easy to construct, the programming and compatibility/operation with the Spartan Chassis equipment might be the hard part.

The DSS was originally designed for Spartan and then adapted to FL so you shouldn’t have any problems. Back when it was developed the parts were under $100

 

[Freightrain]

I have recently purchased a 2015 Dutch Star on a Freightliner chassis. Is the a simulator available to bypass to get me off the road if I have a def issue?

 

[Rich W.]

I have recently purchased a 2015 Dutch Star on a Freightliner chassis. Is the a simulator available to bypass to get me off the road if I have a def issue?

No. Pre 2016 emissions are not compatible with the DSS and a lot of 2016 coaches are on 2015 chassis so even they have 2015 emissions. And it’s not just the plug difference which was the initial problem adapting the DSS (designed for Spartan) to FL. That issue was easily solved because it was just the plug and the electronics were essentially the same.

But pre-16 systems are a lot more on the analog side of things (an electronics expert I am not). The good news is that the pre-16 system don’t have the QUAL (DEF quality) sensor which was a weak link in the system causing headed failures for several years. Also the level sensor in the pre-16 systems is mechanical (a simple float) so it is often to easy to solve errant “low DEF” issues which would otherwise derate you and could leave you stranded.

So the short answer (guess I could have just started with this) is that while the DSS won’t work for you, you also don’t have that much need for it. Below is a link to the TSB on the FL DEF header tank level issue and the typical fix. I’ve also seen accounts of people flushing the tank several times with hot water to clean the float assembly and resolve the issue without pulling the DEF header.

https://static.nhtsa.gov/odi/tsbs/2013/MC-10142383-9999.pdf

Another common problem with pre-16 DEF headers was tank heater valve failures. When the valve fails, it fails in the open position (dumb engineering decision) so if it opens errantly it cooks the DEF at engine temp which degrades it to the point that it no longer functions in the SCR so once again, you DEF temp warnings and/or low DEF warnings when your tank isn’t empty. The fix is to either by-pass the tank heater (since you probably don’t need it anyway) or if you plan to operate in sub 12° F weather (unlikely) you can install a manual valve on the supply side. There is ample info on this available and it is a simple cheap fix.

 

[Rich W.]

Because he’s selling my intellectual property that I offer to Owners for free. He has no right to sell my IP. If folks want to change folks $75, I’m fine with that since it does take 10-15 minutes to build one.

Thanks for the straight answer on this. I was shocked when I saw the $600 price tag, but decided to stay out of it. Maybe it’s different/more involved for Volvo systems? I don’t know but I hope Spartan and FL owners aren’t paying that much for a DSS.

Most of what I post about this is from memory during the R&D phase (before I was banned from that other site) so please feel free to fact check/correct any info I post about it. I understand the systems failrly well but the electronic side is, and will remain, a mystery to me.

My goal, like yours, is to simply help people get through the emissions debacle rather than being stranded and spending ridiculous amounts of money to fix problems caused by bad policy and insufficient engineering (had to step back on my soap box for a moment). But my abilities stop far short of the EEE side of things.

 

[Freightrain]

No. Pre 2016 emissions are not compatible with the DSS and a lot of 2016 coaches are on 2015 chassis so even they have 2015 emissions. And it’s not just the plug difference which was the initial problem adapting the DSS (designed for Spartan) to FL. That issue was easily solved because it was just the plug and the electronics were essentially the same.

But pre-16 systems are a lot more on the analog side of things (an electronics expert I am not). The good news is that the pre-16 system don’t have the QUAL (DEF quality) sensor which was a weak link in the system causing headed failures for several years. Also the level sensor in the pre-16 systems is mechanical (a simple float) so it is often to easy to solve errant “low DEF” issues which would otherwise derate you and could leave you stranded.

So the short answer (guess I could have just started with this) is that while the DSS won’t work for you, you also don’t have that much need for it. Below is a link to the TSB on the FL DEF header tank level issue and the typical fix. I’ve also seen accounts of people flushing the tank several times with hot water to clean the float assembly and resolve the issue without pulling the DEF header.

https://static.nhtsa.gov/odi/tsbs/2013/MC-10142383-9999.pdf

Another common problem with pre-16 DEF headers was tank heater valve failures. When the valve fails, it fails in the open position (dumb engineering decision) so if it opens errantly it cooks the DEF at engine temp which degrades it to the point that it no longer functions in the SCR so once again, you DEF temp warnings and/or low DEF warnings when your tank isn’t empty. The fix is to either by-pass the tank heater (since you probably don’t need it anyway) or if you plan to operate in sub 12° F weather (unlikely) you can install a manual valve on the supply side. There is ample info on this available and it is a simple cheap fix.

Thank you for your response. What does SCR and TSB stand for?
Also, can you recommend a code reader for this 2015 Dutch Star? I had a small one for my 2014 Ram. Very useful. Then I had it deleted.

 

[Roadglide117]

I talked to a guy that build them and leases them, illegal to sell them. He told me analog systems, you are wasting money to have one, it will never get used.