Heater works, No Defrost

[MainePellethead]

Hey all:

Can some one answer a question for me...

My son has a Mazda 626, he called me, says his heat part works on his car heater but when he goes to put it on defrost, its not working. I havent had a chance to look at it for him so dont know any more details than that til he comes over for me to look at. Any ideas?

Appreciate it...Thanks.

 

[pegdot]

Not a Mazda expert but there's likely a flap in the ducting behind the dash that should move to redirect the air toward the upper vents when defrost is selected. Fixing the flap is no big deal but pulling the dash out to get to it is a pain. If the heat continues to come out at floor level or even moves to other vents when defrost is selected that's likely the problem. If you are really lucky the disconnect could be directly behind the control panel and not buried deeper. I'd check there first.

 

[MainePellethead]

Not a Mazda expert but there's likely a flap in the ducting behind the dash that should move to redirect the air toward the upper vents when defrost is selected. Fixing the flap is no big deal but pulling the dash out to get to it is a pain. If the heat continues to come out at floor level or even moves to other vents when defrost is selected that's likely the problem. If you are really lucky the disconnect could be directly behind the control panel and not buried deeper. I'd check there first.

I kinda was thinking that too....good to get confirmation..lol....Thanks pegdot...appreciate it......my son says it does come out the bottom for heat just no defrost....I'll be looking at it more today or tomorrow.....thanks again.

 

[mayhem]

Agreed its an air ducting door problem. The question then becomes...is it a stuck door or a controller problem. My old 87 RX-7 had a bad controller when I bought it, dealer had to swap it out...it was a very expensive part since it was all electric.

I have a very similar problem in my 2000 Silverado right now. Almost no heat on the floor, fortunately defrost works fine. I'll have to tear it apart in the spring.

 

[MainePellethead]

Agreed its an air ducting door problem. The question then becomes...is it a stuck door or a controller problem. My old 87 RX-7 had a bad controller when I bought it, dealer had to swap it out...it was a very expensive part since it was all electric.

I have a very similar problem in my 2000 Silverado right now. Almost no heat on the floor, fortunately defrost works fine. I'll have to tear it apart in the spring.

I'm hoping its not a controller.....dont think this one is electric....I'll know more when i actually look at it....thanks agaon

 

[MainePellethead]

when all else fails , consider a lighter plugin heater/fan which u can place at the critical spot for vision. mine draws power & i dont run at idle because i'm superstitious, i guess.

Actually....before he got a chance to get it over to me to look at....it started to work again...lol. The car belonged to a 90 yr. old and it sat for a month or so after she died....he got a good deal on it though...only has 45,000 miles on it....barely broke in. So maybe the duct was stuck or something.....not sure. lol....Thanks all for the advice.

 

[pegdot]

I've got an old SSE that has a crazy flap. Switches air flow on it's own when you hit a bump or turn a corner hard. Just can't bring myself to tear the dash out since I hardly ever drive it. Mine only does it with the Ac on though never had it happen with the heat. Cool air does you absolutely NO good coming out the defrost vents in the summer though.....lol.

His was likely just stuck. Hopefully it will never happen again. :coolsmile: