CEL DPF

[todd92]

I assume there is still no way to clear CEL's or force a regen at home when it decides to go into limp mode?

 

[justman777]

Are you sure it's in limp mode because of a DPF issue? What symptoms are you getting?

Here's a link on how to run a manual regen.

I've never had to run a manual regen. I try to keep the RPMs up to at least 1500 when I'm transporting longer distances. Lower if I'm only moving a short distance, and higher when I'm working.

 

[todd92]

I know it's in limp mode, the same thing happened last spring, had to take it to the dealer, they cleared the code and forced a regen and it worked again for a year. The NX only did automatic regens for the 1st year and has needed ever more frequent manual regens ever since. It has 1000 hrs on it now. The CK still does passive regens infrequently at 350 hrs. This time I did a manual regen and it went into limp mode after an hour. It was running fine right up until the CEL, just like it did last year. I just removed the the DPF and I'm going to pressure wash it, it's obviously clogged with ash. It only took 20 mins to remove.

I know what's wrong, I'm just trying to clear the code myself.

 

[justman777]

You could try the old car trick of removing the negative on the battery for a while. See if that clears the code.

 

[todd92]

That has never worked on anything I've tried it on in over 20 years. The ECU has a non-volatile memory, it does not require current to 'remember' codes.

 

[justman777]

Sorry then. Don't know any way to remove the codes except a trip to the dealer, or possibly start/stop cycles of the ECU where the condition that caused the fault doesn't exist anymore.

 

[countrybumpkin]

Try a cheap obd ll reader to clear the code, I cleared my codes when I was have injector issues. The reader would not recognize the code number but it would clear all codes.

 

[todd92]

I did, the DPF code doesn't show up on a normal car OBD2 reader. You need a J1939 protocol HD truck scanner, which my research found 3 moderately priced Chinese knockoffs. I just ordered this one:

Autel ML529HD Autel

I'll report back how it works.

 

[todd92]

I backwashed the DPF with a pressure washer. A ton of black and gray crap came out. I washed it until the water was clear. Dried with an air hose. The substrate appears to be very rugged. I reinstalled it, and for laughs did the negative battery terminal 4 times and of course the CEL is still there. Ran it for a while to see if the code cleared itself, nope. We'll see if the code reader clears the code, otherwise it's the dealer. If I need the dealer, I'll try to convince him to bring the laptop here...

 

[rademamj1]

Power washing should clean out the DPF to an acceptable level for the computer. The CEL must be cleared, either by yourself or the dealer. However just curious, after power washing the DPF, are you still in limp mode?