I'm having the similar issues with my '10, but my car was manufactured in March '10, outside the dates of the TSB for the heated seats. I've had issues starting up the car in the morning, and took it to the dealer a few weeks ago, and they couldn't figure out what was pulling in the power when the car was off. They said that the battery was taking a charge fine. My seats weren't hot, and I figured that it was my V1 powered by the center console. After I moved the V1 connection to the front dash charger, I was ok for a few days, and the last few days the car won't start in the mornings again. I leave the car outside in the cold, it's been in the 20s overnight. I'm not sure what's causing the issue at this point, perhaps the remote starter? I don't know if I should try leaving the car in the garage to see if that makes a difference or not, or if I should stop trying to use the remote starter to see if that makes a difference.
Mazda CX9 -2010 - Battery dead issue
- Thread starter piyushkt
- Start date
- :
- 2022 CX-5 Turbo
If I were you, I would debug this by removing accessories installed after market, either by yourself or the dealers.
This includes those electronics that were installed at the port of entry, i.e. remote starter, HomeLink backview mirror, etc.
Current drain is hard to track down. However, there is a device that you insert into the battery terminal. You
can monitor the current drain while the ignition is off. It should be at mA level.
NOTE: when you disconnect battery, you lose all the "memory" of electronics such as preset radio stations,
window auto open/stop, etc. Be aware of that. You make the call.
This includes those electronics that were installed at the port of entry, i.e. remote starter, HomeLink backview mirror, etc.
Current drain is hard to track down. However, there is a device that you insert into the battery terminal. You
can monitor the current drain while the ignition is off. It should be at mA level.
NOTE: when you disconnect battery, you lose all the "memory" of electronics such as preset radio stations,
window auto open/stop, etc. Be aware of that. You make the call.
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If the dealer can show that the battery has no power drain when turned off, I don't think that would qualify under lemon law.
If your multi meter shows no/minimal power drain while turned off, then this means that likely the battery is not being recharged properly
when running.
Possible causes:
-Loose grounding cable somewhere, or from factory a grounding point may be painted on accident
-Bad alternator
-Bad engine wiring harness (which has happened on a few cx-9's...but usually the bad harness has not produced dead battery)
Do you leave your lights on auto? if so even if they appear to turn off, maybe they turn on in the middle of the night? try turning them "off" ?
Deffinately take to another dealer if you are getting nowhere with the current one.
This should not be a hard issue to diag.
If your multi meter shows no/minimal power drain while turned off, then this means that likely the battery is not being recharged properly
when running.
Possible causes:
-Loose grounding cable somewhere, or from factory a grounding point may be painted on accident
-Bad alternator
-Bad engine wiring harness (which has happened on a few cx-9's...but usually the bad harness has not produced dead battery)
Do you leave your lights on auto? if so even if they appear to turn off, maybe they turn on in the middle of the night? try turning them "off" ?
Deffinately take to another dealer if you are getting nowhere with the current one.
This should not be a hard issue to diag.
I just tried again, won't start manually in the car, and tried it with the key and not the smart key.
I do leave the lights on Auto, I'll move the car in the garage and move it to Off, and see if that makes a difference.
I also notice now that it tries to flicker the Xenon headlights only when trying to start the car once, and that it has a hard time starting after 12 hours of being off in the cold.
Since it takes a while to reproduce if I drive it to a dealer, another option is to leave it off in the cold, have AAA tow it to the dealer in a morning, so that they can diag it while it can't actually start.
I do leave the lights on Auto, I'll move the car in the garage and move it to Off, and see if that makes a difference.
I also notice now that it tries to flicker the Xenon headlights only when trying to start the car once, and that it has a hard time starting after 12 hours of being off in the cold.
Since it takes a while to reproduce if I drive it to a dealer, another option is to leave it off in the cold, have AAA tow it to the dealer in a morning, so that they can diag it while it can't actually start.
