06 Escalade. The rear heat stopped working. Unfortunately the control module at fault was discontinued so I went with a new aftermarket Dorman product. The heat is back, blend doors work, but the fan now has a mind of its own. Blows after shutting off engine. Blows on high, rather than slowing to a stop reaching desired temp. I contacted Dorman about this, they asked me if I had any body control module codes. U codes. I was unable to answer whether or not i'm "communicating with the BCM". Until i can answer that they won't exchange or refund me. I have a innova 3040d that reads odb2, abs and oem enhanced codes. I've seen brake switch codes, transmission codes, things that are deeper than odb2. but I've never seen a u code/BCM code or however they are referred to. So my question is do I need a special scan tool/reader to see these codes, or should a decent odb2 code reader be able to display these.