Battery drain due to ventilated seats (2019-2022 CX-5)

[cz5gt]

Anybody had any problems with battery draining because of the ventilates seats not turning off?
i.e car is off but the ventilated seats keep running. Usually after prolonged use of the ventilated seats function (i.e and hour or more in hot weather)

 

[GTEyes]

I haven't had this issue on my past 3 Mazdas with vented seats. I do daily trips where I run them for over an hour.

 

[chickdr]

If they continue to run after the car is turned off, you clearly have an issue which needs attention at a dealer. Are you still under warranty?

 

[cz5gt]

Yep, definitely an issue, just wondering if more people have experienced it. Thanks.

My 2nd CX5 is under warranty so it should be covered..first doesnt have vented seats.

Just found Mazda has a new TSB.
Adding it here in case other folks start to experience this in the future.
Seems the vent seats computer is flawed and has to be replaced.

 

[chickdr]

Nice work! I was not aware of the issue.

 

[GTEyes]

Good find, @cz5gt!

 

[cz5gt]

When my battery went to 6V it got me curious what is going on and started digging.
I have the 2nd cx5 for 8 months and never had issues but I also didnt use the ventilated seats much until recently.
Thankfully its a deep cycle AGM so it survived with a recharge after.

 

[Bullit69]

Did anyone notice if fan stays on after turning off car does the light stay on too so you can see its still on or do you have to listen for the fan? Thanks

 

[cz5gt]

Listen for the fan. btw Not all cars will have this defect.
Ventilated seats have to be used for extended time (hour or more) and in very hot weather. That was my case when it happened.
The problem is the seat warmer/ventilation control unit. Replacement is with new unit which is under passenger seat.

 

[Bullit69]

Listen for the fan. btw Not all cars will have this defect.
Ventilated seats have to be used for extended time (hour or more) and in very hot weather. That was my case when it happened.
The problem is the seat warmer/ventilation control unit. Replacement is with new unit which is under passenger seat.

Thanks, this is Daughters car would just be easier for her to look at light to see if on instead of listening for fan. Reason I was asking as car hasn’t started two weekends in a row where it sat for 24 hours and battery was around 8-9 volts for no reason. Used charger to charge battery and started fine every day until second weekend and was just searching for reason. Load tested battery that was built Sept 2025 and it is not the problem. Will ask her to listen for fan when she turns off. Thanks!

 

[cz5gt]

buy a cheap clamp meter and measure Amps draw.
Open hood, close doors ... wait 15-20 mins and measure. should be very low...otherwise something is sucking battery dry

if its the seat unit, disconnect and measure again. Its easy. it can also be left disconnected if that is the problem but could be other things.What year is the CX5?

 

[Bullit69]

buy a cheap clamp meter and measure Amps draw.
Open hood, close doors ... wait 15-20 mins and measure. should be very low...otherwise something is sucking battery dry

if its the seat unit, disconnect and measure again. Its easy. it can also be left disconnected if that is the problem but could be other things.What year is the CX5?

2019. Thanks will look for meter