2012 Cascadia DD15 Codes

So spn 4364 Is Nox Conversion efficiency low, will initially give you a 25% derate on the engine, this could happen for a few different reasons, anything from intake throttle control all the was to the egr system turbo and all could cause it. Most of the time people end up replacing NOX sensors and doing a regen this is how you verify the repair if everything is good or not if anything else is needed. you have to go step by step and see what the fault codes are active or inactive and how many times it has happened, need to check def and see if def quality is good a lot of time that is the problem as well. the other fault you have is for blower motor in the cab probably drawing to much current.

 

I don’t think that will work unless it fixed itself. It could derate u more if conversion efficiency is not how it’s supposed to be. Better take your chances of driving straight home. U can do a regen yourself did u try that.

 

Putting the unit on a low temp ATD test will determine if your NOx sensors are working correctly or not. You will need to unplug the DEF doser also during this test.

 

Those Cascadia blower motors fail, but are easy to replace. You can do it yourself. I think mine was $150 if I remember correctly.

Here's a video...

 

If you don't take care of that NOX error SOON ... you will derate to 5 mph. The first derate is 25% reduction in power, next is 55mph, then 5mph. DEF quality is rarely an issue, but the system"assumes" that if NOX conversion efficiency is down then it is either a bad sensor or bad DEF. DEF metering unit can go bad and cause this also.

Much of this is dealer only stuff. I hope you find a dealer that knows that they are doing, some will just replace parts over and over until the problem goes away. Others have techs that can interpret the computer data and use their experience and solve the issue quickly and at the least cost.

 

Also there are two NOX sensors, input and output, so you need to know which to try to replace. Usually end up doing both.