That's interesting. Pretty good mek-a-nik!

I wish your signature was filled-out. What truck do you have?

My 2015, was covered. It was after the bumper to bumper ran out. Dealership still fixed under warranty. I already considered myself quite fortunate, at the time.

 

2014 Silverado LTZ Dually, used to pull a heavy tool crib all over western Canada. I figured it was still under warranty, but they called in and were told that nothing in the def system was covered.

 

That sucks, man. It's a common problem. And, they should cover it, IMO.

Mine only took a couple hours, the first time.

Yeah, I was headed home, with a new heater and the DIC said low quality DEF detected, reduced power in blah blah blah.... I said, Oh hell, no! Went back and something had gotten screwed up during the heater replacement that took two days to track down and repair.

They gave me a loaner though. I didn't have work at the time. So, all was well with the world. I got to drive a crappy little half ton around. Made me appreciate my pickup.

 

burred: Hopefully, this link works. I guess this is how mine was covered. It looks like yours should be, also.


https://gm.oemdtc.com/6957/29400-sp...overage-adjustment-diesel-emission-fluid-tank-reservoir-2013-2015-chevrolet-gmc

 

Temp fix

How did your mechanic install a light bulb in place of the heater circuit? I'm limited to 55mph as of today until I can get the part in on Thursday. I'm not sure if it will even last until then before it goes into limp mode? This dpf stuff is bs, I'm doing a delete asap. Go figure, I'm at 128k so warranty won't cover it

 

I am going to attempt the bypass today. If it works I’ll let you know how it goes.

 

Ordered 2.2 ohm resistors to put in line. They will be in on Tuesday. Spent 5 dollars on them. I am going to try and make a comprehensive video on this work around. I’m going to only leave it until I delete. I have had a new def heater in there for a year and it broke. It seems like every year I have had to put a new unit in there. What a trash part.

 

I dropped the tank yesterday, unplugged the def heater (there are only two wires going directly into the def heater/sending unit module. Red and white wires.)

I unplugged that and clipped the wires back far enough so that I could have them hanging out when tank is back in.

(I got my 2.2 flameproof resistors in the other day off amazon)

On the clip that I took off I stripped the wires and put the resistor in line and taped it up really well.

I then plugged it back into the plug that is for the def heater.

I reassembled the def tank and put it back with the wires hanging out on the visible passenger side. I did however tuck them back into the cover for the tank.

You get 8-10 resistors in a pack. I made the whole thing quick release in the case that it ever goes out. I made a few extra resistors and threw them in the glove box just in case.

I know not everyone can afford a 2500 dollar delete kit right away and some of us are tired of putting sh** parts back inside of our vehicles that cost a lot of money.

So far everything is working. I cleared the codes and drove it around town for several hours.


Pending any issues I will post if I have them. I’m not seeing any though.

The reason this all works is because the heater has a 2-4 ohm resistance that it sends back to the computer and says “hey I’m working”. The heater is the same as a probe in your hot water heater for your home. Sometimes they bust, sometimes they get out of resistance due to temperature of the fluid in the tank. That triggers the light and trouble code to come on. So this fix is just saying “hey the resistance is right. It’s at 2.2-2.5 ohms.”

Please understand that this turns the heater off completely. So if you live in frigid temperatures, it will freeze the fluid and it will not thaw.

 

I know this thread is over a year old now. The reductant heater 1 in my 2011 just took a crap with code P20B9 and I tried to bypass it with a 2.2ohm 1 watt metal film resistor. When commanding the the active test on all three heaters, the test for open circuit on heater one all of a sudden kept showing fail and would not clear. Aparrently when commanding test it burned up the resistor.
My question is, what type of resistor and what wattage did you use to fix this? I refuse to keep installing heaters as well when I live in Central Florida and will never worry about frozen DEF!
Any wisdom shared with the same experience would be greatly appreciated.

 

Can you post some pics or send them to my email so I can see what you did I just got this code and I would like to try this until I can get the deletes for my truck. My email is Adam.douglas22@yahoo.com. Also when you hooked everything back up how did you clear the service exhaust fluid system message? Did you have to go to a dealer or use a special scan tool to clear it

 

Power equals voltage squared divided by resistance. If the DEF heater is drawing the full 14 volt battery supply, square that value (196) and divide by the resistance (2.2 ohms), which gives you 89 watts. So use a 100 watt 2.2 ohm resistor. Your 1 watt resistor was much too low of a power rating and it burned up.

 

Thanks for the help! I didnt think that the 1 watt would be a problem being it wouldnt draw to much current but totally over looked the power consumption. This makes total sense, already ordered new 100 watt resistor. It looks like a big sucker, has an aluminum heatsink shell encasing it. Im assuming this will work fine. I appreciation the electrical lesson.

 

Or a 100 watt 12 volt light bulb.

 

I appreciate the help guys, I had found a 2.2ohm 100watt resistor on amazon with aluminum heatsink. Will give it a try, it should work. If not a light bulb it is.

 

Update: I installed the resistor mentioned above and secured it up above frame to where heat from aluminum heatsink could dissipate. Had shop with Autel run the three reductant heater tests and this time bye bye 55mph limit from def light. Thanks for everyones input. Hopefully it will last.

 

So I just got the same code, did you cut the two wires and wire them both to the resister? Or just wired it in series with one of the wires? Can you take a pic please.

 

Is a scanner tool required?

 

Yes you need an autel or snap on, etc than can run the reductant heater test which is the only way that i know can clear the message and limp mode

 

I HAVE A 2014 DURAMAX WITH 31,000 MILES ON IT.
THE CODE SHOWED UP , P20B9 ON MY WAY TO WORK, STATING 99 MILES TILL SPEED LIMITED TO 65 MPH, THEN, 70 MILES TILL SPEED LIMITED TO 55 MPH, ACCORDING TO THE #'S IN 40 MILES I WILL BE LIMITED TO 55 MPH. I AM PARKED BOUT 150 MILES FROM HOME . NEW REDUCTANT HEATER JUST ARRIVED AT HOME.

QUESTION # 1 IF I REMOVE THE BATTERY CABLES. WILL THE COMPUTER RESET AND TAKE THE SPEED LIMIT OFF, W?
QUESTION #2. WHERE EXACTLY DID YOU PLACE THE RESISTER IN THE CIRCUIT, IN LINE OR ACCROSS BOTH THE WIRES ? PIC'S?
QUESTION #3 ARE THE WIRES ACCESABLE WITHOUT REMOVING THE TANK?

THANKS
BILL

 

I HAVE A 2014 DURAMAX WITH 31,000 MILES ON IT.
THE CODE SHOWED UP , P20B9 ON MY WAY TO WORK, STATING 99 MILES TILL SPEED LIMITED TO 65 MPH, THEN, 70 MILES TILL SPEED LIMITED TO 55 MPH, ACCORDING TO THE #'S IN 40 MILES I WILL BE LIMITED TO 55 MPH. I AM PARKED BOUT 150 MILES FROM HOME . NEW REDUCTANT HEATER JUST ARRIVED AT HOME.

QUESTION # 1 IF I REMOVE THE BATTERY CABLES. WILL THE COMPUTER RESET AND TAKE THE SPEED LIMIT OFF, W?
QUESTION #2. WHERE EXACTLY DID YOU PLACE THE RESISTER IN THE CIRCUIT, IN LINE OR ACCROSS BOTH THE WIRES ? PIC'S?
QUESTION #3 ARE THE WIRES ACCESABLE WITHOUT REMOVING THE TANK?

THANKS
BILL

You cannot clear message by disconnecting battery, has to be done by diagnostic tool.

You are eliminating the heater out of the equation so you have the wires as close to heater as possible and connecting resistor in series (in place of heater). I was able to access without totally dropping tank. Loosened straps and bejng supporting by floorjack just lowered it a bit for access. Shouldnt take any longer than an hour to accomplish the work. Sorry dont have pics.

 

Thank you

 

This is an old topic I know...but stupid question here. What if you DO live in a cold climate? Will this fix still work as basically a hard wired def bypass/delete? I'm ok with the def fluid freezing and not actually being able to be used. Don't care...just want the error message to go away and want my truck back out of limp mode.

 

but if i read this right.. you light bulb provides the load feedback to the ECM of what the heater would do.. what happens when your DEF is frozen and the vehicle cant keep NOX within limits.. won't that throw codes that will put you in limp mode?

 

I was thinking my understanding is that there is a def sensor that is reading the temperature. And actually disables the entire def system if the temperature is low enough that it's frozen. The heater turns on when this happens, and is on for 270 minutes, and the def system is enabled again once the sensor reads that there is no longer any danger of the fluid being frozen.

So basically by jumping the heater with a resistor, it gives the illusion that the heater is working fine, but the temperature never gets above freezing per the def sensor. So in theory, the entire def system just stays disabled because of this. So basically it's just like the heater is on but can't keep up so the def system stays off.

 

Absolutely F-ing brilliant!! That is by far the best solution that I have every heard of for this complete DEF nightmare. I have deleted plenty of trucks in the past but not everyone can afford to delete, so this is an absolute genius solution!!

 

Can I ask what will happen to the filter when you drive the truck for some time and the spot builds up? Isn’t the reductant system specifically designed to help bake the soot out?
I absolutely love the idea of this trick, but I’m not sure if it will last very long before the soot levels are through the roof. What to do then?

 

The reductant system is designed to remove contaminants in the exhaust gas, does not have anything to do with the soot caught by the DPF.

 

You have to run a system tamper test with a scan tool.. The ECM needs to see everything is working properly and then the message will clear..
You can drive it and it will run a self test also.. The message will not clear if the ECM sees a problem.