DEF light,check engine light on

[GregorYahu]

Maybe replace DEF Tank

Have a dealer look into replacing the DEF tank under warranty. I had some issues, replaced the heater assembly, all kinds of sensors, to no avail. Turned out to be a DEF tank problem that GM has extended the warranty up to 120k miles.

Happy new year everyone.As stated in the title the lights came on while traveling from NY to central Florida.The camper ran fine ,we stopped south of Jacksonville for a quick stop and when I got back on 95 the lights came on.Got very nervous.Wlfe made multiple phone calls asking for advice,but being a friday afternoon before the holiday averyone was shut down till tuesday,even the 24/7 direct help line from Freightliner. 24-7 direct ????,What the heck.WE continued on our trip at highway speeds of 70 mph and stand stills and the truck ran fine for the remainding 150 or so mlles. Have been doing tons of research,driving myself crazy with worry.
I have read about Lines being crossed possibly,Ect.Truck has 20,000 miles with no previous problems.
Any help greatly Appreciated

 

[subvet-THOR]

Rusty,thanks for all your help.The mechanic tested the truck for codes and he found faults in the def header.He is cumming to the rv tomorrow to install a new head.I will ask him to trace the lines.If they are crossed can they be switched at the def head ?
I also found a DEF simulator on ebay,Maybe a good idea for insurance?
Again,thanks Rusty,

 

[Rustynuts]

Rusty,thanks for all your help.The mechanic tested the truck for codes and he found faults in the def header.He is cumming to the rv tomorrow to install a new head.I will ask him to trace the lines.If they are crossed can they be switched at the def head ?
I also found a DEF simulator on ebay,Maybe a good idea for insurance?
Again,thanks Rusty,

The place they are connected wrong are on the inside of the drivers side frame rail where they connect the the frame rail bulkhead fittings. The lines are easy to trace up to the point where they cross over from the passenger side to the drivers. The best way to trace them is to mark the hot supply line with a marker or paint pen every 6” and make special note where they pass through a cross member and turn 90 degrees, the hot supply line should turn and still be the forward most line. If you look at the pics of mine, the hot supply line comes through the cross member and then was placed in the band clamp in the rearward position and then they continued across and connected the hot supply line to the return line bulkhead fitting inside the frame rail, not the front bulkhead fitting like it should. If doing this you are still not sure if it is correct, the fail safe way to check it is to remove the hot supply line from the fitting on top rear of the engine and then remove the front line off the bulkhead fitting on the frame and blow air in one end and if air blows freely through the supply line it’s correct.

Here is the link to all the line drawings.

 

[Rustynuts]

If you are at all handy and can solder and crimp wires the simulator is simple to build for about $35 with all the parts available from Digikey last time I looked and takes about 15-20 minutes to build. The unit is great insurance from getting stranded but if you use the unit, understand that you still have to keep def fluid in the tank as the system will still operate as normal, the unit is just simulating the sensors that are on the header and telling the ecu that things are normal. The unit simulates the 32.5% def concentration, the def temp as ambient temp and the level at 75%.

Here is the main simulator website.
https://defsim.myervin.com/

Info on the latest and simplest build
https://defsim.myervin.com/canbed-rp2040-def-sensor-simulator

Info on the SPECIFIC plug needed from out Freightliners.
https://defsim.myervin.com/dss-connector-plug-for-freightliner-chassis-xcm

 

[javamon-JAY]

If you are at all handy and can solder and crimp wires the simulator is simple to build for about $35 with all the parts available from Digikey last time I looked and takes about 15-20 minutes to build. The unit is great insurance from getting stranded but if you use the unit, understand that you still have to keep def fluid in the tank as the system will still operate as normal, the unit is just simulating the sensors that are on the header and telling the ecu that things are normal. The unit simulates the 32.5% def concentration, the def temp as ambient temp and the level at 75%.

Here is the main simulator website.
https://defsim.myervin.com/

Info on the latest and simplest build
https://defsim.myervin.com/canbed-rp2040-def-sensor-simulator

Info on the SPECIFIC plug needed from out Freightliners.
https://defsim.myervin.com/dss-connector-plug-for-freightliner-chassis-xcm

How difficult is it to get to the sensor plug to plug in the simulator?

 

[subvet-THOR]

Thankyou Rusty,going to give it my best in the morning....

 

[Rustynuts]

How difficult is it to get to the sensor plug to plug in the simulator?

Very easy to get to. Open the drivers door and remove the 3 screws out of the panel below the door opening and the def header and plug is right there. This pic is looking at the def tank with that panel off on my S2 chassis

 

[subvet-THOR]

Not that handy with electrical stuff,found one on ebay that I think will work.I'm sitting in a rv park with hardly any tools,1200 miles from home.
One more huge favor can you check out the ebay item #355225289842,option1
If you think it will work I will order one.
Many many many thanks....

 

[Rustynuts]

Not that handy with electrical stuff,found one on ebay that I think will work.I'm sitting in a rv park with hardly any tools,1200 miles from home.
One more huge favor can you check out the ebay item #355225289842,option1
If you think it will work I will order one.
Many many many thanks....

Yes that one would work fine and yes, option #1 with the Freightliner plug

 

[Jeepin Jason]

Thanks for the pictures Rusty. I am going to double check my 2022 whenever it is done with another winter of warranty work in Vegas.

 

[subvet-THOR]

The tech replaced the DEF header,coolant lines were not crossed.No more codes.
Was able to buy the bypass from ebay.Got a email from ebay saying i MAY have bought an illegal device and they are no longer allowing seller to sell these on ebay any more.
Hopefully the truck is fixed for the journey back home.I did get the bypass as insurance.
Thanks rusty for all your help
Marty

 

[javamon-JAY]

The tech replaced the DEF header,coolant lines were not crossed.No more codes.
Was able to buy the bypass from ebay.Got a email from ebay saying i MAY have bought an illegal device and they are no longer allowing seller to sell these on ebay any more.
Hopefully the truck is fixed for the journey back home.I did get the bypass as insurance.
Thanks rusty for all your help
Marty

Would you please PM me the seller's ebay name or better yet his ebay email address. Thanks!

 

[Jeepin Jason]

Crap, should have purchased one when I first read this post...

 

[Rustynuts]

The tech replaced the DEF header,coolant lines were not crossed.No more codes.
Was able to buy the bypass from ebay.Got a email from ebay saying i MAY have bought an illegal device and they are no longer allowing seller to sell these on ebay any more.
Hopefully the truck is fixed for the journey back home.I did get the bypass as insurance.
Thanks rusty for all your help
Marty

Saying you “may have” is just covering his butt. Many consider it a “grey area” but the Simulator does not alter the emissions system in any way, it is still operating like designed and only simulating 3 sensors to keep you going.

As far as the tech saying the lines were correct, many people including myself were told by techs and Freightliner than our lines were correct……only to discover for ourselves they were indeed crossed. The only way to know 100% is to check yourself.

Did you have to pay out of pocket or did FCCC cover it?

 

[subvet-THOR]

Sorry for the delay on getting back to you,Will look it up.

 

[subvet-THOR]

EBAY is the one that said I 'may have". EBay also took the add off.
I traced the line from the top of the engine myself,not crossed.
Since I am out of warranty looks like i am going to eat the bill.

 

[subvet-THOR]

Javamon the Ebay seller is Sellution Components,Goon luck my friend

 

[subvet-THOR]

I meant GOOD,not goon,so sorry for the typo errer

 

[javamon-JAY]

Javamon the Ebay seller is Sellution Components,Goon luck my friend

Found another source, but thanks just the same. I will post the new source as soon as I receive the simulator and test it out.

 

[mcdanger]

DEF....again!

I fought this out 2 or 3 years ago with a FL dealer and they said they found crossed lines and fixed it. Now I'm having doubts that they may have not fixed it. Are the lines always crossed at the same place or in multiple places? The same place meaning where the 2 lines start the crossover from pax side to drivers side. I hope someone is still reading this thread!


Thanks