P21B0 code comes and goes
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Tuned
Joined: Nov 2011
Posts: 474
Likes: 45
From: Berryville, AR
P21B0 code comes and goes
This happened about 6 weeks ago. I cleared the 3 codes. (U0422:00-28, P21B0:00-AF, P21B0-c) Then, they showed up again about a month ago and again, last night. I’ve been able to clear them, but I have to wonder what is going on. Can the heater fail a little at a time before completely failing? A loose connection could cause that, but the type of connectors are usually pretty reliable. Any thoughts? Has this happened to anyone else?
Hotshot
Joined: Dec 2005
Posts: 10,256
Likes: 7,694
From: Chino Valley, Arizona
my 16 F550 work truck gets the P21B0 code every time it is started if the air temp is cold.
there is a ford program to fix it, I believe 11 years or 120,000 miles.
call your service department and give them your VIN and mileage they will tell you if you are still covered.
there is a ford program to fix it, I believe 11 years or 120,000 miles.
call your service department and give them your VIN and mileage they will tell you if you are still covered.
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Tuned
Joined: Nov 2011
Posts: 474
Likes: 45
From: Berryville, AR
Thanks helifixer! This makes me feel better. I’m on the road right now and wouldn’t want to try replacing a reductant heater until I get home. If a free flash will fix it, that would be great! My truck has 8 years and 61,000 miles, so it would qualify. Thanks again!
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Tuned
Joined: Nov 2011
Posts: 474
Likes: 45
From: Berryville, AR
Hey Guys and helifixer, I found this: https://static.nhtsa.gov/odi/tsbs/20...06862-0001.pdf
However, it sounds like I would have to go to the dealer while the light is on. When I get home, I’ll have all winter for it to come back!
However, it sounds like I would have to go to the dealer while the light is on. When I get home, I’ll have all winter for it to come back!
Hotshot
Joined: Dec 2005
Posts: 10,256
Likes: 7,694
From: Chino Valley, Arizona
not a reflash you get an upgraded heater.
Thread Starter
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Tuned
Joined: Nov 2011
Posts: 474
Likes: 45
From: Berryville, AR
Oh, I see. I now have the code pop up every time I start it. I need to tow my 5th wheel camper from Virginia Beach to south Georgia. Do you think it will get me there? Once there, I’ll have over a week that the dealer can have it.
Hotshot
Joined: Dec 2005
Posts: 10,256
Likes: 7,694
From: Chino Valley, Arizona
my 16 work truck has had it for about 2 months, I just start it and clear the code.
there is a cheap parts store code reader plugged in all the time, I don't even look at it I just hit clear codes after starting.
there is a cheap parts store code reader plugged in all the time, I don't even look at it I just hit clear codes after starting.
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Tuned
Joined: Nov 2011
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From: Berryville, AR
Awesome! Thanks again!
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