DEF System Fault
Super Moderator
Joined: Aug 2008
Posts: 37,384
Likes: 1,868
From: Frederick, MD
There is part of your problem. Frequent unnecessary filling of the DEF gets it confused.
Let it run down till you get a warning of about 200 to empty, then do a complete fill. It will work better.
You may have to take it in for a reset, but drive it for a few days and see what happens.
Let it run down till you get a warning of about 200 to empty, then do a complete fill. It will work better.
You may have to take it in for a reset, but drive it for a few days and see what happens.
Cargo Master
Joined: Nov 2005
Posts: 2,051
Likes: 10
From: TEXAS
My issue is different, the last two times I have gotten the 500 mile to empty. I run it down to where it reads 200 miles plus or minus a hair then fill it up. But, it doesn't even take a full 2 1/2 gallon bottle before it starts overflowing.
It was my understanding that the DEF capacity was closer to 5 gallon total.
It was my understanding that the DEF capacity was closer to 5 gallon total.
Super Moderator
Joined: Aug 2008
Posts: 37,384
Likes: 1,868
From: Frederick, MD
@<200 to empty mine will just about take 5 gallons.
So, something is wrong if it is calling for def and you are getting the count down and it is not taking but a gallon.
So, something is wrong if it is calling for def and you are getting the count down and it is not taking but a gallon.
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New User
Joined: Oct 2017
Posts: 4
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Thanks for your help. I am going to take it to the dealer where I bought it and see what they say.
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Post Fiend
Joined: Nov 2001
Posts: 6,748
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From: Tallassee, ALabama
Did you pull any OBDII codes? That might give you and indication of the problem.
From the 2015 Diesel Owner's Supplement Manual...
Selective catalytic reduction systems are sensitive to contamination of the Diesel Exhaust Fluid (DEF). USE ONLY API or ISO 22241 CERTIFIED DIESEL EXHAUST FLUID (DEF). If the selective catalytic reduction system becomes contaminated or inoperative, the Diesel Exhaust Fluid (DEF) light will illuminate and exhaust fluid system fault messages will appear in the information display.
I would first try pumping the DEF out of the tank and refill with fresh DEF. If still a fault, take to a dealer. It may require a few drive cycles to clear the fault light.
you can get a pump like this at Wal Mart or Harbor Freight to pump the DEF out of the tank...
https://www.walmart.com/ip/Custom-Ac...-Pump/16767856
From the 2015 Diesel Owner's Supplement Manual...
Selective catalytic reduction systems are sensitive to contamination of the Diesel Exhaust Fluid (DEF). USE ONLY API or ISO 22241 CERTIFIED DIESEL EXHAUST FLUID (DEF). If the selective catalytic reduction system becomes contaminated or inoperative, the Diesel Exhaust Fluid (DEF) light will illuminate and exhaust fluid system fault messages will appear in the information display.
I would first try pumping the DEF out of the tank and refill with fresh DEF. If still a fault, take to a dealer. It may require a few drive cycles to clear the fault light.
you can get a pump like this at Wal Mart or Harbor Freight to pump the DEF out of the tank...
https://www.walmart.com/ip/Custom-Ac...-Pump/16767856
Trailering
Joined: Jul 2017
Posts: 15
Likes: 1
Joe-
Read your initial post with much interest. I have a 2012 6.7 that I just purchased to pull my fiver. Got my first DEF warning at 500 miles till empty. At 400 miles till empty I bought a carton of BluDef. It only held slightly over 2 gallons of the 2.5 gal in the box. Warning went away about a day later so I guess all is well.
What I wonder about is why I have a 5 gallon def tank (or so I am told) and I got a low def warning when the tank is still half full?
Hope you are getting your issue straight. Keep us posted.
Read your initial post with much interest. I have a 2012 6.7 that I just purchased to pull my fiver. Got my first DEF warning at 500 miles till empty. At 400 miles till empty I bought a carton of BluDef. It only held slightly over 2 gallons of the 2.5 gal in the box. Warning went away about a day later so I guess all is well.
What I wonder about is why I have a 5 gallon def tank (or so I am told) and I got a low def warning when the tank is still half full?
Hope you are getting your issue straight. Keep us posted.
Posting Guru
Joined: Oct 2013
Posts: 1,039
Likes: 2
From: NC
Joe-
Read your initial post with much interest. I have a 2012 6.7 that I just purchased to pull my fiver. Got my first DEF warning at 500 miles till empty. At 400 miles till empty I bought a carton of BluDef. It only held slightly over 2 gallons of the 2.5 gal in the box. Warning went away about a day later so I guess all is well.
What I wonder about is why I have a 5 gallon def tank (or so I am told) and I got a low def warning when the tank is still half full?
Hope you are getting your issue straight. Keep us posted.
Read your initial post with much interest. I have a 2012 6.7 that I just purchased to pull my fiver. Got my first DEF warning at 500 miles till empty. At 400 miles till empty I bought a carton of BluDef. It only held slightly over 2 gallons of the 2.5 gal in the box. Warning went away about a day later so I guess all is well.
What I wonder about is why I have a 5 gallon def tank (or so I am told) and I got a low def warning when the tank is still half full?
Hope you are getting your issue straight. Keep us posted.
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