2011 Ford F250 filled DEF, but still low warning light

This is one of the more common DEF system errors on the 2011 6.7's...during the first winter, both GM and FOMOCO had tank, tank heater and sensor issues...not a big deal...most of them have been repaired or replaced by now...some more than once...fortunately it is emissions related so FOMOCO can't weasel out of fixing them...

Regards

It is the "heating sending unit" that has failed. This assembly is inside the DEF tank that monitors the level and keeps DEF warm.

Gave them the ok to get the repair done.

Fulltimer50 wrote:
Get to the dealer. They are the only ones who can check the codes. Get ready for a $$ bill. Something to do with the DEF sensors usually.

Ford dealership will attempt a reset/ troubleshoot per service writer and call me later in the day. I will keep you posted.

Get to the dealer. They are the only ones who can check the codes. Get ready for a $$ bill. Something to do with the DEF sensors usually.

Mdamerell,
There is a DEF "1/2 full" signal that comes on instrument panel and does not signal again, until, I believe it is 500 miles that you have to refill or will go into reduced speed mode.

At this 500 mile point, it becomes a system warning...this is what I meant is first low warning light. This is when I filled with 2.5 gallon and it did not clear the system warning.

Thank you sir,

What do you mean by 1st low warning light? I ask because the gages in a semi are normally set up as 4 green blocks (1/4,1/2,3/4,full) The 1/4 light turns yellow as a warning then red before the engine goes into protection mode. They are not the most accurate gages and they do fail. Had to have one replaced a month ago on a 1 year old truck. So it's possible you have a bad gage or a leak since you have added so much DEF. I'd start with looking for a leak. DEF leaves a white crystal residue that's caustic. If you have a leak you need to find it and protect your truck.

Hope you didn't put it in the fuel tank by mistake....