Def fluid pump

[BikerT]

Have the dreaded def fluid countdown going on, Took to dealer, was told needed new pump, $4000 cost. I brought truck home. I was told by someone that because of so many codes showing, P202a, 203, 204 205, to check electrical because it could be an electrical issue, sounds like an entire harness unplugged. I took pump cover off and pulled connection to pump and it was extremely wet inside. Now I am wondering if this could have just shorted out.


I will dry it completely, but hope someone can tell me what fuses etc I might need to check.

 

[MADDOG]

Sorry you are having problems with that problematic DEF system.

Dry that connector out really well. Clear the codes by disconnecting the negative side of your battery for at least 30 minutes. This will perform a PCM reset.

There should only be one fuse for the DEF pump circuit. All your codes are related to the PCM not receiving signals from the DEF system. Here's what the PCM recorded as communication/out of range faults:

P202a is the def tank heater.
P203a/e is the def tank level sensor
P204a is the DEF liquid dosing control circuit
P205a is the DEF tank temperature sensor

Good luck. Let us know how things go.

OBTW, what is a "cummings" ?

 

[Daw14]

I think a Cummings is a bird of some kind .

 

[BikerT]

Ok, ok, my CUMMINS

 

[BikerT]

ok, an update and a few questions, I REALLY need some help. I cleaned and dried plug, and as suggested, removed both negative battery terminals for several hours. Well, after all that, when started, same display, limp mode in 13 miles.

First question, why did nothing reset, not even radio after 3 hours of battery being disconnected? Capacitors that good? But then I read it is not good to disconnect battery.

My next question is if it had been a problem with plug only and cleaning fixed it, wouldn't warning go off on it's own?

I still don't know if it's anything electrical or really the $1000 pump. All I know is my wife and I still have no truck to drive.

 

[TMyers]

My Cummins threw a Service DEF message a couple years ago. The fix was DEF fluid had crystalized on the pumps pickup not letting DEF flow.

As far as a new pump, I'd try to find one at a salvage yard. Or, anyone with a deleted truck has one not being used.

 

[Paul p Smith]

Sub-zero temps here in Central Alaska really create DEF nightmares. Waiting for a backordered pump now.