My heater drains my battery when it is not running?

2000 GMC YUKON
163,000 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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LILBITTYCHICK86
  • MEMBER
  • 1 POST
Okay, so a few days ago I went to start my vehicle and the battery was drained. Weird okay, charge battery I go about life as usual. Until later that evening when I went to run to the store and I opened the driver side door and realized I heard the back heater wigging out, going off and on at random, and it was completely powered off. As a matter of fact, I made sure all the knobs were turned to the off position and it continued to go off and on. I have no clue what's causing this but clearly it needs to be addressed. Thanks!
Jan 10, 2023 at 1:51 AM
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STRAILER
  • ✓Experienced Mechanic
  • 55,256 POSTS
Yep, this happens when the blower motor speed control resistor goes out. here is the location so you can replace it. You will need to remove the plastic from the rear HVAC unit to get to the resistor speed control. Check out the images (below). Let us know what happens and please upload pictures or videos of the problem.
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Jan 13, 2023 at 1:58 AM
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