Audi Adblue Issues - P20BD Reductant Heater Circuit - Engine light on Audi Q5 2.0L TDI

We get an Audi Q5 TDI in with an engine light on due to P20BD. With a little research and testing, we get to the root cause of the issue and get it rectified for the customer. Special thanks to ‪@Diagnosedan‬ who created www.ddtsb.com for the automotive community.