DD13 SPN 3251fmi 21

[Rawze]

(11-13-2025 )Therealarw Wrote:  Hi there guys..

I'm having this issue with one of my freightliners with a DD13 giving me a "DOC pressure not plausible" I've checked all the tubes for the inlet and the outlet. I checked to see if the there was voltage going to each sensor and I got 5 volts going into one pin and 2 grounds(if I unplug from each sensor) I've also run a DOC face cleaning for like 3 hours and the code still came on... I'm just not sure if it got the full cleaning... But this thing has been a pain in my a**, if I'm missing anything please let me know! Thanks

Pull the cans off it and have them professionally cleaned. doing hours worth of 'regens' on the truck does not clean them but about 2-3% at best, and is nowhere near the same as having them properly cleaned in oem-certified equipment.

Also, after they are cleaned properly, there is usually a procedure to reset the 'soot buildup ESTIMATE counters' in the ecm, so that it stops assuming they are still clogged up.