Heater - A/C Blower not working right.

heaven17 · Post by **heaven17** » June 10th, 2006, 1:03 pm

I replaced the heater blower in a 1992 MX3 4 cyl and the fan only works on "4" setting not on 1,2,3 settings, plus the A/C no longer works. It seems that the A/C will go on in the 1,2,3 setting but not 4. I have checked the fuses that correspond to the A/C and the circuit breaker for the heater and everything seems good.

I found a new replacement fan through Napa and it looks identical for $120, Mazda wanted $760. The fan could go closkwise or counterclockwise depending on the electrical hookup, so I installed it then tryied both ways to see which one would blow. Also, I did buy the one for A/C. I guess there's a difference?

Any ideas?

ariesdude · Post by **ariesdude** » June 10th, 2006, 1:09 pm

Probably something wrong with the switch itself - you can try to open it up and clean it and see if anything is broken or get a used one from a junkyard/ebay and replace it.

Grants · Post by **Grants** » June 10th, 2006, 1:12 pm

Huh? You replaced the heater blower. What exactly is that? The rest of it is a good run down but

I replaced the heater blower

sorta leaves any sensible input out.

so I installed it then tryied both ways to see which one would blow.

They should suck, not blow.

Hope that helps.

heaven17 · Post by **heaven17** » June 12th, 2006, 2:06 pm

Ariesdude , I don't think it's the switch because the air conditioning stops working on the max or "4" setting also, it seems to go on in the 1,2,3 settings (but at this setting the fan doesn't work).

fan setting 1,2,3 = air conditioning works but fan DOESN'T work
fan setting 4 = no air conditioning but fan DOES work.

Grants, the heater or a/c blower blows trought the vents, I think you confusing it with the cooling fans under the hood. Or maybe the fans turn in reverse in Australia like your toilets LOL

Thanks,
Scott

ariesdude · Post by **ariesdude** » June 12th, 2006, 5:59 pm

heaven17 wrote:Ariesdude , I don't think it's the switch because the air conditioning stops working on the max or "4" setting also, it seems to go on in the 1,2,3 settings (but at this setting the fan doesn't work).

fan setting 1,2,3 = air conditioning works but fan DOESN'T work
fan setting 4 = no air conditioning but fan DOES work.

The A/C switch is inter-connected to the fan switch - its a safety feature to prevent turning the a/c on without the fans on. (If you dont believe me - Please consult the wiring diagram from Grant's site). So if there is something wrong with the fan switch it might explain the weird a/c behavior too.

Looking at the wiring diagrams - it looks like In your case the resistor that controls the blower speed is not connecting to the blower motor properly (the "4" setting bypasses the resistors - but the resistor is still needed for the a/c to work) - the resistor is located inside the switch assembly - best bet would be to replace the switch assembly for say $10 off of ebay or junkyards.

heaven17 · Post by **heaven17** » June 13th, 2006, 2:01 am

It makes sense, I did replace the fan motor only after it ceased so maybe it burned out the switch.

Thanks