OTR Diagnostics, DEF, Derate Faults

[redbaron]

Redbarron thanks for sharing! Shoot... I was hoping for an easier fix.... I'm a full timer w/o a shop/garage which will allow me to change mufflers. I do miss my tools!!!

Back in 1995-99 I was heavily involved with conversion kits with the Impala SS. This involved cat deletes and fake sensors, and modified pipes. I was able to create a pipe replacement that could be done in an hour, and sold those as a kit.

I am thinking this is something that may be necessary for the ISX and ISL. I don't have a Spartan chassis (yet) so it will be a while before I do start this project.

I am hoping to get an answer to the prior question of is this necessary, or can we develop a documented procedure to disable limp mode *when* the failure occurs. That would be preferential, as no changes are required to physical equipment.

This is very easy to create--once I have a spartan chassis. To create the scenario, unplug the def head and drive. It will eventually go into limp mode and create the red stop alert. Then you have to figure out how to override this--with the cable unplugged still.

If someone is as daring as I am, feel free to reach out to me for specifics of what is required--etc. You will be at risk for needing a tow

 

[tims5842]

I keep mine running while fueling just so I don’t become “that guy” with a no-start in the truck fuel lane.

There is actually a good reason to leave the engine running. Shutting down a hot turbo is bad for the turbine and the exhaust manifold. All turbo engines should idle for a good period of time to "cool down" gradually before being shut off. Keeping them running in the fuel line helps prevent a rapid temperature change in these parts and extends life. Bottom line from what I've been taught, you should always idle down a diesel motor for at least 5 minutes before shutting down.

The other issue here with the DEF heads is that there has been some speculation about derate intervals being tied to not only mileage, but also on/off cycles. So the fewer key turns you have, the theory is less chance of the derate occuring if you have one or more error codes already in the system.