Heater issues on a 93 k3500 turn signal as well

[stevejohnson48]

Originally Posted by Racer2172

This post is a question to try and help my dad on his truck. He has a 93 k-3500 extended cab with a 5 speed and 454. His issue is the following on the heater when selected to the hot side no hot air the blower is working fine just no hot air cold only. Also his left turn signal is not working. Any input on this would be greatly appreciated.

There's a cold and hot air flap that's regulated by a little servo motor on my 90 silverado (called a regulator motor)if this motor is bad or the flap is stuck in one position or the other it will cause the problem??/ and then there's the other possibility that the control panel is not sending the proper signal (mostly on the digital control units that do that??/)To That regulator motor that controls the hot and cold mix hope this might be some help although its not the same year vehicle??/