What Chevy Man can answer this ?
 

Here's the deal:

When using the A/C, low and medium speeds worked fine, but when switched to "high speed" the blower motor just stoped blowing (didn't blow fuse)

* I thought it might be the high speed fan relay so I replaced that, now when I turn on the A/C, low and medium work as before but when I switch to "high" it pops the fuse "20amp". (didn't pop when using old H/S fan relay)

* I assumed the new high speed fan relay was bad and returned it for another new one only to find it doing the same thing.

* I unpluged the inline power condensor to the blower motor and it still poped the fuse when I turned A/C to "high".

* I unpluged the blower resistor and still poped the fuse when switched to "high".

I haven't tested the control panal in the dash yet, but was wondering if anyone had any other good ideas ?


:fb:

Check the fan switch in the dash, on mine the wires were melted and the switch was burnt.... But, I only had high speed and no others.

I will check that Saturday, thanks Bro.

Anyone else ?

look at the blower motor fan, possible resistance either mechanical or electrical that is drawing too much of a current when you switch it to high and that since its a current overload, is blowing the fuse, is you truck a glass fuse or plastic blade fuse type?

Fuse is a plastic plug in yellow 20amp.

Think maybe the blower motor could be shorting this thing ?

i would try unplugging the blower motor itself and put a DMM in place of the motor, so you can see if your getting voltage, and with the DMM in place, just see if your getting power there (most likely 12v at the high setting) and if it blows with the blower motor not connected its a short IMO, if it doesnt blow when the blower motor is disconnected, reconnect it and try, if it does then, its most likely the motor, at which point i would go buy another blower motor and plug the new one in and see if it does still pop

if ya do all that and it still blows, lemme know and ill look at teh schematic to see if it oculd be something else

full foot notch
Thanks Bro I will check it out and ost back.......

Yeah sounds like the switch... mine doesn't work on high but on the rare occasions i throw the switch back and forth really quick, sometimes it'll jump into high.... :crazy:

My dash bezel is just so brittle, so i don't take it off unless i gotta :)

cliffsta I will check the switch also.

BTW cliffsta why do you hate your life ?

LMAO I dunno. It was a joke. :)

Basically, kinda like, whenever life sucks, i just jump in my truck and go for a joy ride.

You could complete my avitar by making it:

I hate my life.... when i'm not in my truck :)

Fair enough, lol.................

so you figure it out yet baldmike

No not yet, I had to do a family thaing Saturday.

I hope to check out the fan switch and some other things Sunday or Monday.

All I know is it's too damn hot with no air, lol..........

you might check the wireing harness to the blower ,a/c, heater unit see if there is a wire that is opened and shorting it out

Check the blower motor common problem when the motor is bad. I know the problem in GM G Body cars 90% of the time it was the blower motor.

Well I'm down to checking the blower motor itself,must be it ?
Will post back, and thanks to all.......

There is a relay outside under the hood where the blower bolts up. Change the relay and you should be set.

Are you talking about the high sped fan relay or the tube shaped relay ?

I already replaced the H/S fan relay.......