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I have a P205B code, a P21AB code, aP21BO code, and a P203D
I have a P205B code, a P21AB code, aP21BO code, and a P203D code, what parts and sensors do I need to make this repair to clear out the codes and get my check engine light to go out. I look up that I … read more
Gm Tech (Cam)
Gm Tech (Cam)
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Vocational, Technical or Trade Scho
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On a 2012 gmc truck with a 6.6 Diesel engine and 2500 it
On a 2012 gmc truck with a 6.6 Diesel engine and 2500 it says service exhaust fluid system and 71 miles till 55 mph top speedSo I scanned it and P20B9 code and I cleared it but still nothing and it's … read more
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I had a code p20b9 come up last week so I took it to a local
I had a code p20b9 come up last week so I took it to a local shop. They replaced the reductant heater check engine light went away … read more
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JOHN aka Eauto
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2011 GMC Sierra p205D and U029D looked over wiring found no bad connections or bare wires … read more
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My service exhaust system message with the mileage countdown
My service exhaust system message with the mileage countdown wont reset … read more
Gm Tech (Cam)
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I have a 2011 GM Sierra 3500hd with the duramax lml engine.
I have a 2011 GM Sierra 3500hd with the duramax lml engine. I have a service exhaust message and another that says on next fill up I will be limited to 4 MPH. I think the problem is the reductant heat… read more
Gm Tech (Cam)
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Vocational, Technical or Trade Scho
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I have a 2016 gmc diesel I got a warning light-to Service
I have a 2016 gmc diesel I got a warning light-to Service Exhaust fluid system.With no check engine light I brought it to my local shop they changed the two heaters one line heater and one tank heater… read more
Expert
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2012 gmc denali 2500 duramax. the "service exhaust fluid system" indicator came on. went to max xpeed 65, then to max speed 55, now in 65 miles it will go to 4mph. Had a bad battery and changed it. Ha… read more
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Def light won't reset after adding fluid and speed has been
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Service exhaust fluid light came on read the code and it
Service exhaust fluid light came on read the code and it said reluctant heater we replaced that but do not know how to reset the system, engine is limited to 4 mph. … read more
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I have a check engine light that shows the reductant heater
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I have a 2013 GMC Denali Sierra HD and it shows engine codes
I have a 2013 GMC Denali Sierra HD and it shows engine codes p205B and p21DD. I know both deal with reductant heater issues. One is the heater and one is the sensor. If the sensor fails, will that sho… read more
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My 2014 GMC 3500 displays "service exhaust fluid system"
My 2014 GMC 3500 displays "service exhaust fluid system" speed is now limited to 65 mph … read more
Gm Tech (Cam)
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Filled def tank and still won't go over 55 How do you reset
Filled def tank and still won't go over 55 How do you reset it? … read more
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I spend a lot of time on the road. i am retired. i usedto
I spend a lot of time on the road. i am retired. i usedto design and build 12V and 24V control systems. This winter my DEF started giving me strange readings. the tank was at 14% and it took maybe 1 g… read more
Expert
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Service exhaust fluid system see owner's manual. Speed
Service exhaust fluid system see owner's manual. Speed limited to 55 miles an hour talk to GMC dealer he said it needed a new exhaust fluid tank because some of the sensors were bad couldn't just chan… read more
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Gm Tech (Cam)

Gm Tech (Cam)

GMC Mechanic

2,015 satisfied customers

GM Grand Master Technician 2007. 14 year experience.

Gary

Gary

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Chris (aka-Moose)

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Don - Mo Lurch

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Mike S.

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Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

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