Common questions

Why does my Blazer blow air to the floor?

Why does my Blazer blow air to the floor?

My 1999 S10 Blazer LT 4.3L 2WD with computerized climate control will not switch air flow to the floor. I have defrost and top-vent all of the time no matter what position the switch is in, but not to the Floor.

Can a climate control fan only blow defrost?

SilveradoSierra.com • Fan Only Blows Defrost, Won’t Change To Floor Or Vent. : Climate Control Fan Only Blows Defrost, Won’t Change To Floor Or Vent.

Is the Astro fan only blows defrost?

Re: Fan Only Blows Defrost, Won’t Change To Floor Or Vent. Yea the problem with them astro’s is the way the damn motor is crammed into the dog house with the heat it destroys the hard plastic vacume line . I have had 5 of them and every one had this problem until you change them out with rubber lines .

What to do if your GM fan won’t defrost?

See if this fixes the problem. Many of GM’s AC control heads have a built in reset feature that when power is removed and then applied it will go through a cycle that activates all the vent doors and mode doors. It’s worth a try.

Why are my front vents on my Chevy Trailblazer not working?

Recently my front vents stopped working on my 2004 Chevy Trailblazer. I’ve tried to recalibrate by taking out the fuse, waiting a couple minutes, putting the fuse back in, turning the car to run, letting it go through its motions, but that didn’t work. The air blows cold, but it is only coming out at the feet, side vents and defrost.

SilveradoSierra.com • Fan Only Blows Defrost, Won’t Change To Floor Or Vent. : Climate Control Fan Only Blows Defrost, Won’t Change To Floor Or Vent.

Why is the pass vent on my heater not working?

There is a blend door in your heater and it’s either stuck or not working. It ‘s electrical or vacuum. You can reach your hand under the dash and see if you can move it one way or the other. You should be able to see if it will start to put the pass vent cold or not.

See if this fixes the problem. Many of GM’s AC control heads have a built in reset feature that when power is removed and then applied it will go through a cycle that activates all the vent doors and mode doors. It’s worth a try.

Why does my heater not change the temp?

The temp control switch is only switching temps half the time. Sometimes it will work sometimes it wont. I can turn it back and forth from hot to cold and it will not change the temp coming out of the vents. Its random, sometimes just playing with it for awhile will get it to work. Any idea what it could be? Hoping its just the switch.

Is there a problem with my AC heater?

Im Having problems with my trucks heater/ac. The temp control switch is only switching temps half the time. Sometimes it will work sometimes it wont. I can turn it back and forth from hot to cold and it will not change the temp coming out of the vents. Its random, sometimes just playing with it for awhile will get it to work.

What causes a heater head to fail on a car?

It failed (ruptured diaphragm) and allowed oil to be sucked into the vacuum lines. This oil caused the switches/actuators inline to also fail. They also mentioned heater control head problems as a result, I believe (sorry, going from memory).

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Ruth Doyle