How do I fix my truck heater to blow on the floor?

My advice would be to call a mechanic friend. There could be a number of reasons the floor heat doesn't work, a mechanic would be able to give you the best information and suggestions to try.

These types of functions used to be done by engine vacuum but now they are done by small electric motors. One of these motors must have gone bad.

I would contact the Chevy mfg. (you can do it online) and they can help you out. I couldn't find a good answer for you in my research.

Found this info.; If it is like the 2002 Blazer it is vacum controled. A small hard black hose on the Driver's side under the hood goes thru the fire wall and to the AC switch/ vent control on the dash and then to a control box on the driver's side under the dash. There are two hoses going to it (red and green) Check your vacum and then to get at the switch, take off the lower and upper plastic covers. Good luck. ANOTHER i had recently had the same issue. anoother cause is the hvac(heat, ventilation, Air conditioning) module is bad. basically all i did was go to a junk yard and got another control unit and hooked it up. the whole control unit in the dash was easily replaced and in under half an hour. it is a common issue in the 01 and 02 models for it to stop working properly.

23 people found this helpful. hope this helps

Happened to our jeep. A hook came loose that controlled the panels.