"Service DEF System" P206D Code - Reductant Quality Sensor Circuit High Voltage

[DGT]

CEL came on and the dash flashed "Service DEF System - See Dealer". The scanned code is P206D. Although this code could be a wiring issue, in my case, the DEF sensor located inside the DEF tank is bad. Unfortunately, this sensor going out requires an entire "new" DEF tank (the sensor is not serviceable). I have an appt in late January for replacement under warranty.

My symptoms were that this code occurred three times over two weeks after shifting into 4x4 Low. When the code appears, within a couple of minutes, the DEF level defaults to 100% full. The code has never occurred when NOT in 4x4 low, and has appeared every time I've been in 4x4 low since the code was first thrown. If I clear the code after shifting out of 4x4 low, the code does not reappear until I shift back into 4x4 low. This leads me to believe that if an owner was not regularly using 4x4 low, the sensor could go bad without throwing the P206D code. (that's a guess, but the service advisor did say the appearance when using 4x4 low is a key sign it's the sensor and not a wiring issue).

Hope this helps someone that has this code appear. I haven't seen it mentioned before in this forum.

Sponsored

 

[NewbJLUOwner]

CEL came on and the dash flashed "Service DEF System - See Dealer". The scanned code is P206D. Although this code could be a wiring issue, in my case, the DEF sensor located inside the DEF tank is bad. Unfortunately, this sensor going out requires an entire "new" DEF tank (the sensor is not serviceable). I have an appt in late January for replacement under warranty.

My symptoms were that this code occurred three times over two weeks after shifting into 4x4 Low. When the code appears, the DEF level defaults to 100% full. The code has never occurred when NOT in 4x4 low, and has appeared every time I've been in 4x4 low since the code was first thrown. If I clear the code after shifting out of 4x4 low, the code does not reappear until I shift back into 4x4 low. This leads me to believe that if an owner was not regularly using 4x4 low, the sensor could go bad without throwing the P206D code. (that's a guess, but the service advisor did say the appearance when using 4x4 low is a key sign it's the sensor and not a wiring issue).

Hope this helps someone that has this code appear. I haven't seen it mentioned before in this forum.

Hey, sry to hear this. Coule quick questions
At what mileage did this happen? What year is your Eco-Diesel?
Under factory warranty? What is warranty on the DEF tank?
Glad its under warranty and will be fixed soon
Thanks

 

[DGT]

Hey, sry to hear this. Coule quick questions
At what mileage did this happen? What year is your Eco-Diesel?
Under factory warranty? What is warranty on the DEF tank?
Glad its under warranty and will be fixed soon
Thanks

I'm at 25k miles, 2022 JLURD, so it's covered under the regular 3/36 warranty. I don't know if it would be covered past this warranty under the standard extended emissions warranty. That's a good question.

 

[rickinAZ]

I'm at 25k miles, 2022 JLURD, so it's covered under the regular 3/36 warranty. I don't know if it would be covered past this warranty under the standard extended emissions warranty. That's a good question.

I would guess that this repair would fall under the eight-year emissions warranty since the whole point of having DEF is emissions control. That said, occasionally I venture to my closest dealer (Airpark Jeep in Scottsdale), usually when I want to test my sanity. Their knee-jerk reaction was that my faulty DPF was not covered under the emissions warranty. I then retreated to my favorite, but less convenient dealer (AutoNation Jeep), and had it replaced no questions asked.

I honestly had high hopes for Airpark when Berkshire Hathaway bought the chain that owns their dealership. Evidently, some things can't even be fixed by Warren Buffet's magic touch.

 

[BDinTX]

Can't think of why 4 Low would have any effect on a DEF sensor. Please let us know if replacing it resolves the problem.

 

[flick2614]

4Lo is obviously the factor, but the link to DEF is really blurry. Is it possible that shifting into 4Lo gives some indicator to the ECU to either increase DEF usage or cut it off, triggering some kind of variable use sensor? Did you happen to notice your actual DEF level when it happened?

I can't wait to tear the stupid DEF system out.

 

[DGT]

4Lo is obviously the factor, but the link to DEF is really blurry. Is it possible that shifting into 4Lo gives some indicator to the ECU to either increase DEF usage or cut it off, triggering some kind of variable use sensor? Did you happen to notice your actual DEF level when it happened?

I can't wait to tear the stupid DEF system out.

After the first instance, I did look at the DEF level on the dash and also what the Scanguage measured it at. Dash showed just above 75%, scanguage said 72%. I've now driven it a couple hundred miles as this error has recurred two more times, and the DEF is at 65%, so it seems to be using more DEF than usual. 50 miles of that 200 was in 4-low. Good question of whether more DEF gets used per the computer while in 4-low.

 

[flick2614]

After the first instance, I did look at the DEF level on the dash and also what the Scanguage measured it at. Dash showed just above 75%, scanguage said 72%. I've now driven it a couple hundred miles as this error has recurred two more times, and the DEF is at 65%, so it seems to be using more DEF than usual. 50 miles of that 200 was in 4-low. Good question of whether more DEF gets used per the computer while in 4-low.

50 miles of 200 in 4Lo? Damn I'm envious; wish I could put in that many miles in crawler mode.

 

[zouch]

did you try simply topping off the DEF?
could be the issue is showing up on 4-Lo because it’s sloshing around.

 

[BDinTX]

After poking around on the internet... I'm leaning towards battery issue causing implausible data. It's no crazier than my Fuel in Water indicator coming on because of a weak battery...

 

[Ratbert]

50 miles of 200 in 4Lo? Damn I'm envious; wish I could put in that many miles in crawler mode.

Try doing the Rubicon. It'll be two to three days and not 50 miles, but 100% in crawler model.

 

[DGT]

50 miles of 200 in 4Lo? Damn I'm envious; wish I could put in that many miles in crawler mode.

Yes, one of the advantages of living in Southern Utah!

 

[DGT]

did you try simply topping off the DEF?
could be the issue is showing up on 4-Lo because it’s sloshing around.

I have not tried topping off the DEF. I'd think 2/3's full would not cause problems, but that's an easy thing to try. I'll try it! Who knows!

 

[DGT]

After poking around on the internet... I'm leaning towards battery issue causing implausible data. It's no crazier than my Fuel in Water indicator coming on because of a weak battery...

I've had no battery issues, but I am still on OEM original batteries, and small battery is still in place. Since I can reproduce the CEL code by just going into 4 low for a few minutes, I am able to try different things and see if the CEL doesn't come on after any of the adjustments.

 

[Coreyb516]

I'm at 25k miles, 2022 JLURD, so it's covered under the regular 3/36 warranty. I don't know if it would be covered past this warranty under the standard extended emissions warranty. That's a good question.

How far are your trips it doesn’t seem like you drive a lot

Sponsored