Looking for some help guys. I’ve got a well used 2012 F250 6.7 with 113k miles. I had the DPF cleaned and replaced all EGT sensors as well as the pressure sensor. I reset the DPF learned values with Forscan and cleared a couple of EGT related codes. Now its throwing a P2455-ac code on initial start up. Clear it and soon as it cranks it there again. I was wondering should I also do the SCR Converter learned values reset as well? I know there is a wealth of knowledge on this forum and any input would be greatly appreciated!!

 

P2455 - DPF pressure sensor A circuit high. Did you install a new Ford DPF pressure sensor? If not, put the old one back in or get a new Ford one. Is it plugged in? Was this code there before having the DPF cleaned?

 

Code was not there before cleaning. I bought a Standard brand replacement. Ford version is about $400 more. Everything is plugged in. I did both the SCR & DPF learned resets. I followed my techs’ guidelines to check voltage levels on plug and it is at 5 volts. Range is 4.5-5.5 according to the shop manual. Wiring looks good with no change in voltage while moving wires to check for short. I have another sensor coming in the morning. Hopefully I just got a bad sensor on the first try.

 

I assume you have a scanner capable of showing live data? Put the old sensor back in if you have it. Aftermarket emissions sensors for diesels are garbage. There is a reason the OEM ones cost a lot more. As for testing, having 5V on the BU/BR wire is correct but that is only 1 wire of 3. P2455 sets when the DPF pressure sensor signal voltage is at or above 4.9v for more than 15 seconds. If you can monitor data, look at the DPF pressure voltage PID to see if it is showing 5V.

 

I’m using Forscan on my laptop. The original sensor got broken after removal for cleaning. I’ll see what I can find on Forscan after I get the new one tomorrow. I really appreciate the help. I’ll post with the results.

 

If you have any input about using Forscan to see PID please let me know.

 

Did you reset the DTC in FORScan?

 

Yes, I did reset the DTC. So, for the update, I did get another sensor yesterday morning and it didn’t fix anything either. Code come back with all sensors even the original. Since then I have checked continuity of the wiring to see if there were any short between the wires or to the truck. Everything checked out good with the wiring in that respect. Should I fork out the almost $500 for a new FOMOCO sensor? Is it likely that the PCM has an issue? Has anyone got any ideas on what my next step should be? All advice is appreciated!!

 

I also looked at the PID for the voltage on the sensor and it never changed from 5 volts.

 

If the code wasn’t there before and the circuits test good, the replacement sensors are likely defective. There is a reason why we only use OEM sensors at our shop.

 

Thanks for the reply Evan! I’ll post an update when I have new info.

 

So, I checked the wiring harness for shorts and continuity and all checked good. Looked at the PID on Forscan and the voltage never wavered from the full 5 volts. I came to the conclusion that the sensor must not be connecting since the voltage never changed. I studied the plug and socket on the sensor depths and decided it must not be traveling far enough to connect. The plug would mate together and the retainer would snap in place so I thought it was far enough, but I was wrong. After getting aggressive with the plug it traveled home in the socket and that’s all it needed. Cleared DTC and voltage on PID was about 0.7 volts idling. Sorry for the delay in posting the update. Unfortunate life events got in the way. Thanks again for the guidance!