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I have a check engine light that shows the reductant heater…

Customer Question
I have a check...

I have a check engine light that shows the reductant heater sensor is difective

Mechanic's Assistant: Does the light stay on, or does it blink?

It stays on. Reading on internet it appears to be a common problem

Mechanic's Assistant: What is the model/year of your GMC?

2015 silverado crew cab

Mechanic's Assistant: Are you fixing your Silverado yourself? What have you tried so far?

Just researching will have my mechanic fix it if this is not a recall issue. Do not want to have to replace the tank assembly

Mechanic's Assistant: Anything else you want the mechanic to know before I connect you?

That's it

Submitted: 7 months ago.Category: GMC
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Answered in 2 minutes by:
12/15/2017
GMC Mechanic: Ron, ASE Certified Technician replied 7 months ago
Ron
Ron, ASE Certified Technician
Category: GMC
Satisfied Customers: 38,580
Experience: 35 years in the Automotive repair business.
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Hello. My name is ***** ***** I am happy to assist you today. Give me just a moment to review your post, and I'll be right back with the help you need.

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GMC Mechanic: Ron, ASE Certified Technician replied 7 months ago

Can you tell me what the actual fault code it is that is setting ?

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Customer reply replied 7 months ago
P205c I believe
Customer reply replied 7 months ago
P205b is the code
GMC Mechanic: Ron, ASE Certified Technician replied 7 months ago

The code P205C indicates a problem with the Reductant Tank Temperature Sensor circuit reading low voltage and in most cases, this is due to a failing Reductant Tank Heater. So are you also getting a code P205B?

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Customer reply replied 7 months ago
I went and it's just the p205b code
GMC Mechanic: Ron, ASE Certified Technician replied 7 months ago

The code P205B set in most cases due to a failing Diesel Exhaust Fluid Temperature Sensor. To verify if in fact the case have your mechanic run the steps in the link below.

https://www.dropbox.com/s/ljaglmbwurltnbu/Heat%20sensor%20Dec%2015.pdf?dl=0

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Customer reply replied 7 months ago
Thank You
GMC Mechanic: Ron, ASE Certified Technician replied 7 months ago

Your very welcome and thank you as well. Please take a moment to rate my service at the top right hand side of the page so I can get credit for my time, the question remains open for follow up even after doing so, all you need to do is return to this question if need be.

Thank you again

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