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flynryan115
08-17-2018, 07:48 PM
Anyone know what this is and where its located? 2013 sprinter 2500
dealer tells me its shorted out.
Thanks for the help

showkey
08-17-2018, 08:26 PM
Ask the dealer.........could be they mean the DEF tank, heater, pump assembly???

flynryan115
08-18-2018, 01:38 AM
8 weeks ago they put in new def pump. Def count down came on Count down took it to them they said pump neeeds replaced . Now it came on 1200 miles later/8 weeks or I should say Sunday so I took it in the said pump was bad again warranty it out and still on now they say adblue control module is out 1900 again. I said no.
Thinking it's the control module on nox sensors.?

lindenengineering
08-18-2018, 03:37 AM
8 weeks ago they put in new def pump. Def count down came on Count down took it to them they said pump neeeds replaced . Now it came on 1200 miles later/8 weeks or I should say Sunday so I took it in the said pump was bad again warranty it out and still on now they say adblue control module is out 1900 again. I said no.
Thinking it's the control module on nox sensors.?

Caution here.
Yes it might be the NOx sensors but the DEF system should be rechecked.
I had one just like yours several weeks ago and diagnosed with a dosing injector faulty.
When I pulled it out it had a big clump of congealed DEF deposits on the nozzle.
As customary I drained the tank refilled it with fresh DEF fluid, installed a new dosing injector , adapted it, taught it all in, did resets etc and it ran like a champ with a good NOx reduction percentage of over 75%.
Two weeks later its back
TWO starts left a hard un-resetable fault.

Starting again with this time a heater fault in the module, the system was re-drained and checked . Again the dosing injector was plugged up!:thinking:
A delivery test showed the DEF pump was working and developing 5000 HPa, but the qty delivered was way out of whack, flooding the bazooka tube (SCR cat).
Replacing the injector under warranty we noticed the flow was a bit erratic.

So as a precaution we rigged up a small pump with some plastic tubing and purged the delivery hose from the DEF pump to the dosing injector with hot water.
Well total amazement!!!
The hose was restricted by a gelled like substance, possibly congealed DEF fluid in a 4" slug like pellet ! Well that is what it looked like!

Once re-assembled we were able to make it all come back to life and the NOx reduction was in the order of 80 plus %.
So a new shop policy
ALL DEF delivery and injection systems MUST be purged with hot water and a 30 psi pump before re-assembly before final proving.
Dennis

Bobnoxious
08-18-2018, 04:31 PM
...big clump of congealed DEF deposits...

Maybe contamination by wrong fluid! Does DEF congeal?

lindenengineering
08-18-2018, 08:01 PM
There must have been a reaction to something in the fluid.
At this stage we are still hoping to find another incident specimen to actually test the fluid.
But in any case a the policy in my shop from now on will be the hot water flush as stated.
Dennis

flynryan115
08-19-2018, 02:15 AM
They said the new pump was not the problem it's the control module not telling it to come on ?
New module installed 1900. but the key thing they said was we hope his is the problem. Yes they are a Mercedes dealer.
But the fault code is still in there p20f5

lindenengineering
08-19-2018, 02:48 PM
They said the new pump was not the problem it's the control module not telling it to come on ?
New module installed 1900. but the key thing they said was we hope his is the problem. Yes they are a Mercedes dealer.
But the fault code is still in there p20f5

Well first we are not doing the job in your cases so its hard to make actual on the job observation and test examples.
That stated we know that if a major component is not coming to life it won't communicate.

Citing examples from last week.
Rig had two starts left and we couldn't re-set it--No comms to the DEF control module. Faults remained--insufficient DEF delivery & NOx output too high. Starting blocking at 2 starts remaining .
OK checked relay and fuses array to DEF module under seat GOOD.
Replaced DEF module --heater fault.
Unit would not re-set a hard fault .
Remove dosing injector and test--recently replaced again covered in crystals--check delivery of fluid now too high! Warranty out the injector.
Re-test using new dosing injector--output erratic & slow to prime up with the scanner.
Investigate --plastic like deposits from pump OBSERVED, connector pipe partially plugged up with gelled DEF fluid!
Puzzled !!!:thinking:
Nevertheless in frame, purge lines & DEF pump with pumped hot water and clear all evidence of gelling.
Re-connect and test--working !
Re-adapt and "teach in" clearing all faults !
Bingo!
Module comes back to life and is communicating with the ECM/PCM.
Start inhibition limits erased subsystems restored. faults cleared
Road tests showed it all working & unit cleared for delivery to customer.

Clearly from our experiences historically active faults must be cleared before a re-learn. A major component malfunction of any kind will leave the rig incommunicado with the module in many cases.
You have to be methodical in both the repair and diagnosis activity on this stuff, and how you attempt to clear the fault( s) -there are many steps to this . skip/overlook one and in most cases it stays locked out.
Dennis