My 2010 Mazda 3 heater fan only works on 4, I expect it is the resistor, does anyone have any suggestions on how to replace it? The 3 is still under warranty, but it is 85 miles to the nearest dealer and I thought if it was fairly simple to fix I would do it myself and save a wasted day in the service area.

Tom

 

There is a resistor pack, which is probably your issue... though i've heard it's a pain to get to, needing you to pull a lot of the dash apart to get to the blower.
Being under warranty, i'd bring it back to them - also ask for the old part, if there's evidence of corrosion so soon it could indicate there is a leak somewhere. Warranty will also log that there was a problem, since if it happened so soon it may happen again, and therefore may be covered under the warranty repair form the last time they replaced it (as if they didn't do it right and that work should be warranteed).


If you do want to get to it, I can tell you on my 2007 (previous style to yours) there is some access to see where the fan is at least from the footwell. There are plastic panels towards the center of the car from the foot wells. Pull those and you can see where the blower is - look for the wiring and see what you'd have to pull out to get to it.
Good luck.

 

Thanks for the reply! I did take it back to the dealer (two trips since they didn't have the part in stock) and they did replace the resistor in the fan motor, which was a pain to get at. I was going to replace it my self since it is 85 miles to the nearest Mazda dealer, but I didn't want to deal with the getting to the fan issue even though it would have been far less expensive to buy the part compared to the gas cost for the trip to the dealer.

This is the third vehicle I have had this problem with, one Nissan, one Chevy and now a Mazda. It seems the car manufacturers would make the resistor easier to get at since it seems to be the weak link in the heater/AC system.

Tom