no blowing air on high

[mudrider420]

i got a 2000 3/4 ton obs chevy and i have low, medium, but no high. can anyone tell me what is the possible culprit?

 

[Luke]

Check the fuses.

 

[Bigg G]

That's a well known issue in GM Trucks

My guesses would be 1 of the following

1)Bad High Speed Relay
2) Bad Blower Switch
3) Possible Bad Blower Resistor but if I remember correctly you only have high speed when it goes bad
4) Burnt/melted connector in the blower harness or at the resistor

I'm sure others will chime in with pics and how to find the fix . In my case it was a little bit of everything going on and then my blower finally took a crap on me. Word to the wise.......don't delay fixing it because that 1 problem has the potential to create other problems down the road.

 

[mudrider420]

well i know the fuses are good (the one inside the cab and outside by the motor). i dont know where the relay would be at exactly.blower switch ,not too sure what to do to check that. i also heard about the resistor controlling low and medium, not high. but i guess i can wait patiently for the pics and fix, but not too long as winter is coming and i know ill need to get it fixed before the snow comes.

 

[2tone95]

check relay,and the ac controls it should be either one

 

[daddy_dandy]

The blower switch is located behind the ac control board and is connected to the back of the fan switch. (The harness on the right of the pic is the blower switch) IIRC, they cost about $20 at your local parts store. You have to remove the front bezel of the dash, then remove the ac controls. Finally, remove the pigtail and the screw which secures the switch.

I recently replaced my blower switch because I only had low and high speeds. Took about 5 minutes to do. But, then again, I've taken the dash apart a million times.

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[mudrider420]

i finally figured it out. it was a loose wire by the blower. i was replacing the relay when i accidently moved the wire and it came on. so i put the old relay back on it and it still works. now i just to figure out the power locks dilema.