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Check engine light, code P21B0 what is it?

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Old Oct 2, 2013 | 09:44 PM
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Check engine light, code P21B0 what is it?

CEL came on.. hooked up my cheap OBD/CAN scanner.. getting code P21B0..googled it and this is what i find: P21B0 - Reductant Level Sensor C Circuit High

what is this for? I've about had it with this truck..this having to replace a sensor every time I take it on a long trip stuff is getting ridiculous..2 EGT's, air charge cooler sensor, blower motor, and now this...
 
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Old Oct 3, 2013 | 06:24 AM
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Have you tried to clear it and see if it comes back?
 
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Old Oct 3, 2013 | 11:03 AM
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That would be another sensor. DEF level sensor.
 
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Old Oct 3, 2013 | 03:59 PM
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yup... cleared it and it comes back again.. off to the dealer...again....sigh...
I would love to delete all of this emissions crap...but I don't trust this truck at all for reliability and don't want to void the warranty..thing would probably drop a valve or blow a rod the day i voided the warranty
 
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Old Oct 3, 2013 | 04:09 PM
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I think the deletes make it a much more dependable truck.
 
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Old Oct 3, 2013 | 04:11 PM
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Originally Posted by Hdslider
I think the deletes make it a much more dependable truck.
For sure, deleted mine at 3,000 miles becuase of CEL crap. 70,000 miles now and not a single (CEL) issue since. Warranty was doing me no good with a truck I could not drive........
 
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Old Oct 3, 2013 | 04:49 PM
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I haven't seen another cel since I tuned mine. Had 2 before that, never shut me down, but had to bring it into the dealer to have the bad sensors replaced.
 
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Old Oct 3, 2013 | 08:07 PM
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I had my first CEL last week at around 90,000 miles. My reader said no codes, I stopped by Autozone, their reader also showed no code, but they cleared the CEL before I could stop them.
1700 miles later, the CEL is back on. I'm back in town and will try to get it sorted out tomorrow.

The messages above have me thinking it might be a DEF sensor as the CEL came on shortly after getting an "800 mile exhaust fluid" message (first time ever) and this was pulling out of Loves after just filling the DEF, the message went away on its own a few hours later.
This morning I started getting the same "800 miles" message, off and on about every half hour. It would count down mile for awhile, then show full again (which it is). Anyway the CEL appeared while I was stopped and checking out everything related to the DEF.

Apparently I need a new code reader, this one worked on everything else I've used it on, it always worked on my 7.3L

P.S.
Maybe a delete would make more sense than a new code reader

Update: The CEL appears to have gone away on its own...
 
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Old Oct 6, 2013 | 02:21 AM
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Truck has been at dealer 3 days now.. No calls, no status updates..they are closed Sunday.. If they don't call Monday then I will have to call them.. And they aren't going to like it if I have to call them..
 
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Old Oct 6, 2013 | 07:29 AM
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Buddy sorry to hear about the issues...I've owned my truck since May 2010 and the the only thing I've had is a blown cold air charge hose (common problem)...My truck has been deleted for 35,000 miles...Love it...I tow a pretty large fifth wheel for around 12,000 miles of the 50,000 miles it currently has.

GOOD LUCK!
 
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Old Oct 6, 2013 | 03:42 PM
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From: Spokane, WA
Good luck to you.

My CEL has come and gone several times the last few days. I can't even get it into the dealership before next week, couldn't get them to just read the code for me. Looks like I'll be doing the next couple thousand mile with that light on the dash, unless I can get it in somewhere else...
 
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Old Oct 7, 2013 | 05:56 PM
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called dealer today, truck was almost finished when I called.. they had to replace the entire DEF tank.. something about the heating element failed...will post more details when I pick it up..
 
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Old Oct 7, 2013 | 06:44 PM
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picked the truck up, and they did replace the whole DEF sending unit/tank...the sender/heating element failed..and I guess it's integral with the tank..
 
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Old Jul 12, 2014 | 11:21 PM
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Originally Posted by mebe2k
picked the truck up, and they did replace the whole DEF sending unit/tank...the sender/heating element failed..and I guess it's integral with the tank..
I know it's been a long time, but do you happen to remember what the bill came to? My truck just threw this code yesterday and my powertrain warranty has expired, so I really hope they don't have to replace the whole tank if it's expensive (I assume it is...).
 
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Old Jul 12, 2014 | 11:28 PM
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Originally Posted by 2ndStroke
I haven't seen another cel since I tuned mine. Had 2 before that, never shut me down, but had to bring it into the dealer to have the bad sensors replaced.
Any "deletes" or are you running just the tuner?
 
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