Low DEF warning with 3/4 tank

I'am in the same boat with 2012 t700 with 336974 turned off the truck came back turned it on lights came out def tank 3/4 full low diesel exhaust fluid on green orange and red engine lights on some one help lol

 

Have you tried filling it?

 

We have had similar issues in a Volvo, sometimes disconnecting the negative cables on the battery for 5 minutes resets it enough to run for a while.

 

I have same problem any one can help i am in truck stop now

 

I have same problem anyone can help am in truck stop now. Thanks

 

I had same problem on same truck. The dealership has replaced 2 def hoses and a sensor. Happened to break down right at a KW dealership. But I just left from that dealer thinking everything was good to go. Got to receiver shut down. Bam! Ref light and derate. Of course not so lucky this time. Mine will run fine for 50-70 miles then just all of a sudden just switch to low diesel exhaust fluid. The gauge will go all the way down and start bouncing. It would derate for 10 seconds or so then pick back up like it never missed a beat. It did that a couple of times then just wouldn't leave derate status.

 

I just fixed mine with the low DEF fluid issue. I had all the code deleted and re flashed the software in after-treatment and ECU. Was bringing up codes for the knock sensor and according to Kenworth when any issues arise in the system it throws that low DEF fluid warning.

They hooked it up a scanned everything and put the update in it so far so good

 

Going through this right now. I just got a new egr installed today went down 8 miles all of a sudden it shows low def with a full tank.

 

I had that happen in a PACCAR MX 10. Turned out to be the J1936 WIRE HARNESS. It's the brain stem of ur engine, from ECU TO Computer in engine. Cost to repair was over 4 grand!!