Howdy yall,

I got a Chevy Trailblazer automatic with about 200,000 miles on it. The radio works, AC works, drives nice, and only has minor cosmetic damage to the interior. However, when I took off the negative lead of the battery it has a parasitic draw when the car has been shut off for around 2 hours, of 5 amps measured by a multimeter. I checked the fuses, and they point back to the HVAC/AC control and the radio in the center of the dash. It looks like someone redid the wiring for the radio because the 2006 plugs do not fit whatever year trailblazer they got the radio out of.

I am not smart when it comes to electrical issues, and due to this parasitic draw the battery keeps dying on me. The battery works well, as does the alternator as they have been checked. How do I figure out why the HVAC and radio have such a high power draw when the car is off? I read online that it could be some kind of faulty signal from one of the computers in the car keeping the radio and HVAC on, but I do not know. Or should I just redo the wiring the hope for the best.

Sincerely, Jeff