Not HVAC Afterblow

Dirk Menzel · 2021-05-30T02:22:59+0000

Hi, My 2008 2500HD has a very(!!) slow / low fan noise and servo sounds from the center front console with the key removed. I notice it when I get back into the truck hours or next day later. Thought it might be "Afterblow" at first, but the next morning after driving it? To be clear, it's barely noticable, but there. The servos (vent flaps?) seem to be hunting. I'm getting ready to pull fuses and check current draw. Ideas?

By Dirk Menzel
May 30, 2021 in Ask A GM Technician

https://www.gm-trucks.com/forums/topic/250204-not-hvac-afterblow/

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