1989 Silverado K1500 the A/C clutch want disengage when the truck is not running and the switch is off. I have the wire harness disconnected from the A/C compressor clutch. If you connect the wire the clutch will engage. I have replaced all three relays ( clutch, high fan, low fan) under the dash, does not have any effect. I discoverd the problem when my battery ran down while the truck was setting for a couple days. Charged the battery and it ran down again. Put a new battery on truck when I connected the cables I noticed the clutch kicked in, knew that was my battery problem. Thanks for any help.