One reason why an AC heater fan will not work on a Mazda 3 is that the fan is burned out. It will have to be replaced. However, first check to make sure that you have not simply blown a fuse.
The heater in the CRV Honda is not working . How do I fix this
Why does your ac and heater fan turn off and on
First check your fuse for your AC in your fuse box, make sure it is good. Make sure your cooling fan is turning on when you turn on your AC, if not it could be your fan relay. If the AC compressor fan clutch is kicking on and off then it just needs freon. If the AC compressor fan clutch is not turning then it could be completely out of freon due to a leak, or you need a new AC compressor.
Which fan is not working? Engine fan or HVAC fan?
If you don't have power to your heater or ac fan, it could be a fuse or a relay. You should check your owner's manual to determine which fuse or relay affects your fan.
I have the 1994 Mazda 626 LX and it has it
Check the fuses.If not the fuse, test the resistor down by the blower motor.
You've got trouble with your heater fan - or the motor that turns it. Same fan for both heat and AC.
There is only one thing you can do if your Heater in your car is not working. You will have to take it to the dealership and have them look at it.
Is your radiator fluid full?
Check the blower motor fuse. Also check the fan relay and resister pack, If all of these are ok then the blower motor probably is bad.
Blown fuse, defective blower motor resistor pack, defective blower motor, or defective fan speed switch.