Problems with HVAC fan

[Zane]

The blower fan on my Zr2 has been giving me FITS since yesterday. It won't run consistantly. No matter what the setting, it will only run a couple of mintues (or not run at all when it starts up), then will shut off, then run, then shut off.

 

I would say over heating, but sometimes i won't work from the getgo.. so

 

I'm thinking sticky relay? because its recently gotten pretty cold here in NH, and it was never a problem before..

 

Any ideas?? ( its cold, i need heeeeeaaaaatttt!!!!)

[Wingnut]

Didn't the Malibu have a billion or so of these go bad? I know my moms did.

 

It was the switch itself that was actually going south and only working when it felt like it, even then, it was only on 1....Or 5...None of the other settings worked.

 

If it's hot, and not blowing, I would start with the switch. If the air stays cold, then I would say check into the cooling system...Low coolant will cause that.

 

But since you say the blower works inconsistantly, I would say electrical. Switch/relay/wiring/etc.

 

My 92s HVAC control panel went haywire and would only work when I held my mouth right had to be taken apart and re-soldered in places. (Much like the winshield wiper fix)

 

Hope it all turns out.

 

[lrymal]

If it is like my '99 Grand Am, the blower motor has a speed control that works via a resistor pack. That pack, when going out, has the problems as you, including some fan settings not working at all, only a couple working, or irratic operation.

 

Not sure if our trucks have a similar resistor pack. Perhaps someone on this list knows and can explain where that pack is and has a part number.

[carl722]

The blower in my ttruck does that. I checked the Blower motor it was fine. I put my multi meter in the wires to it and I got an indication of a bad ground. I went and got a high speed relay and the resistors that change the speeds of the fan and it still did it. It had quit working altogether then I got mad and beat the selector switch on the dash and it started working again but itnermittently. If it quits I push in with a little force on the switch and it starts again. I went to the draler and bought the switch but I haven't had time to put it in yet. The contacts can get dirty or glazed and make it difficult to conduct the electric through the rest of the circuit. I guess the ground contact on my switch is what is getting bad.

[Arisa]

The blower fan on my Zr2 has been giving me FITS since yesterday. It won't run consistantly. No matter what the setting, it will only run a couple of mintues (or not run at all when it starts up), then will shut off, then run, then shut off.

 

I would say over heating, but sometimes i won't work from the getgo.. so

 

I'm thinking sticky relay? because its recently gotten pretty cold here in NH, and it was never a problem before..

 

Any ideas?? ( its cold, i need heeeeeaaaaatttt!!!!)

Hey Mervz

 

What up ??? I had to replace the resistor pack in mine. It would only blow on hi when I bought it. I doubt thatis your problem though !!!

[studly]

I just had an intermittent blower fan in my '98 Blazer.

Sometimes it would work; sometimes it didn't.

The problem turned out to be a bad connection in the

power lead near the fuse box.

[JVinson549]

Some fuse panels use circuit breakers instead of fuses. When a circuit breaker gets weak or overloaded, it will cause the circuit to cycle on and off every few minutes. Could be weak or the blower motor overloading the circuit.