Hi,

Long time 2010 Mazda CX-9 grand touring owner. Hoping for some guidance.

For a few years I thought my rear blower motor was dead and ignored the issue. Finally I did some research and realized it could just be the motor relay. I replaced that in the front relay box and it started working again! It's winter (about 33 degrees today as an example) and I've just realized though, it's only blowing cold air out of the bottom vents in the rear control even when set to absolute maximum. (not to mention "sync") The front is blowing hot air as expected, no issues there.

Any ideas? I didn't see any threads with this specific issue... TIA

 

I had this issue for many years. Then this year our front heater stopped working and it turned out to be a small leak in the radiator that was slowing loosing coolant. Once we had our radiator replaced the rear starting working! So I would suggest checking your coolant level.

As a side note: we used to hear a sloshing sound when the car first started, almost like running water. We no longer hear that sound as well so I'm sure there was a connection.

 

Thanks, it makes sense and I found some other discussion around coolant levels causing this problem. I did check the coolant level and appears I'm a little over the high mark though - so a bit at a loss. Perhaps it's a radiator issue...