I just bought a 2006 GMC K3500 with the LBZ and 114000 miles on it .I have put about a 1000 miles on it and now have a engine light with code P0540 Intake Air (IA) Heater Feedback Circuit.I did a vin check and found out they replaced the glow plug controller right before I bought it ,does the glow plug controller also control the intake air heater? How long does it take to set a code if someone reset it, I was wondering if the person I bought it from knew anything about it?