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Rapid battery discharge

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81K views 136 replies 40 participants last post by  jmwindi  
#1 ·
Hi all! I have owned my brand new Mazda cx30 for 1 week. However, on day two, I drove it home 400km post purchase. After half an hour in my garage, I started getting a flashing warning and beeping on my dash indicating that I was at risk of battery failure, start the engine! My local dealer kept the car over night and recharged the battery (even though I did not feel this would help After driving it that day for over 4 hours) . All was well for 4 days. I was so relieved........This morning I got up and went to start the car. Same message appeared😓 along with beeping for about 10 seconds. I decided to go for a 20 minute drive, reset everything to factory settings. it seems ok for now.3.5 hours later. This is so disappointing as you buy a new car NOT to have these issues occur. I did leave it unlocked in my garage last night with the fob in the house, not the car. Any suggestions? This can not be simply a flat battery issue in a brand new car. just a side note, i noticed that it did not always automatically lock when I walked away From the car.
 
#2 ·
Hi Juliette,

Having the car unlocked in your garage or by accident is a no-go. The electronics in the car keep working in the background and are draining your battery, as you found out. So lock the car even in your own garage. Also having a key (the main key or the spare key) within 7 mtrs of the car, locked or not, keeps a system active in the car because it still "sees" the key. The not always unlocking can be caused by walking away too quickly without having heard a first beep. Hope this helps and you can fully enjoy your new ride.
 
#4 ·
Me too. But you found the other battery topics as well, many possible causes with so much electronics in cares there days. I would also suggest to have your dealer performs software updates on the BMC, LFU, PLG (if you have powerlift gate) and CCU units. There is a recall in Europe for that related to the many flat batteries.
 
#5 ·
I have exactly the same issue and do consider this a software bug, hopefully it will be fixed in the future. It is very annoying. Any other similarly equipped car that I have or had in the past would produce a battery discharge warning after you are really draining battery with no engine running (like listening to the radio, running AC, etc) but this warning would happen like after 10 minutes of the battery being drained but would never happen if you are just having the cabin lights on or similar minor power consumption.

I have the CX-30 Premium Plus for two weeks now and a week ago brought it to the dealer for this exact problem. They ran diagnostics and as expected did not find anything.
But afterwards the service supervisor did some search and found Mazda internal information bulletin which describes exactly this issue. They could not give me a copy since it is internal / proprietary but it looks like Mazda is aware of the problem.

The really scary outage happened to me yesterday. The infotainment screen went dark and I could not bring it back no matter what I tried (after reading similar problem described on this forum). Today I was able to get it back by pressing and holding the mute button.

The other spooky thing I noticed since I was sitting in the car and studying controls with no engine running and ventilation system / AC off was that the air ducts valves are moving opening and closing eventually by themselves once in a while. You hear this specific sound the servo motors produce.

The other thing on my list is that the security light on the instrument panel is blinking even when the car is not locked. I read the manual and it says it should blink after the car is locked which make sense to me. The dealer says that it should blink all the time which looks really strange to me. I wander if other people observed similar behavior.

To be honest, I like the CX-30 a lot but I never had so many issues with the brand new car.
 
#11 ·
Went out to my CX-30 GT Sport Tech yesterday morning, to take it to my local dealers for the freezing mirrors issue (qv) but it wouldn’t start at all, couldn’t even open the boot to get my jump leads out.
Battery voltage was down to about 4v. Got jump started by a neighbour but loads of warnings cycling through in the middle of the Speedo all the way to the dealers.
My wife’s key was in her handbag near a window within arm’s reach of the car. Reading some of the above posts, sounds like this may have been the cause of all our problems.
 
#12 ·
Went out to my CX-30 GT Sport Tech yesterday morning, to take it to my local dealers for the freezing mirrors issue (qv) but it wouldn’t start at all, couldn’t even open the boot to get my jump leads out.
Battery voltage was down to about 4v. Got jump started by a neighbour but loads of warnings cycling through in the middle of the Speedo all the way to the dealers.
My wife’s key was in her handbag near a window within arm’s reach of the car. Reading some of the above posts, sounds like this may have been the cause of all our problems.
Very dangerous to vehicle theft as well being do close to the vehicle..
 
#14 ·
No one have answered the question I posted earlier. The security light is blinking even when the car is standing unlocked in the garage. Per manual it should be blinking only when the car is locked and it indicates that the security system is active. To me it makes no sense at all -- there is no need to have security system running when the car is unlocked. I think this blinking is an indirect indication of the software bug(s) with the car failing to go to sleep mode and this in turn would explain the problem mentioned by OP and I have this exact issue too. The warning indicates clearly that the car did not go to sleep and the battery is discharging. I think the other TSBs may be of a similar nature but not the same problem that I have.

Would anyone care to post whether they have the same issue in their 2021 CX-30 -- the security light is blinking when the car is unlocked and the engine is not running?

Thanks!
 
#15 · (Edited)
No one have answered the question I posted earlier. The security light is blinking even when the car is standing unlocked in the garage. To me it makes no sense at all. Per manual it should be blinking only when the car is locked and it indicates that the security system is active. I think this blinking is an indirect indication of the software bug(s) with the car failing to go to sleep mode and this in turn would explain the problem mentioned by OP and I have this exact issue too. The warning indicates clearly that the car did not go to sleep and the battery is discharging. I think the other TSBs may be of a similar nature but not the same problem that I have.

Would anyone care to post whether they have the same issue in their 2021 CX-30 -- the security light is blinking when the car is unlocked and the engine is not running?

Thanks!
mine blinks all the time when the vehicle is off... that's normal and its part of the engine immobilizer system which is also in the Manuel.. I am in -35 below zero climate here.. My cx 30 has no block and if it did.. no where to plug it in at work as i work nights and get into it at 7 am so its been sitting for 9 hours.. and it is impressive on how well it can start. I don't think the security light is the cause of the battery issues some are having.. my cx 30 is 1 year old and always had the pad lock light blinking when off and I looked it up in the Manuel and like i said that is normal.
 
#29 ·
just got back from my local dealer this afternoon as they contacted me a few days ago to ask me to bring in my CX-30 to have an update on various modules to prevent any excessive battery draw when the vehicle is "asleep". This was a TSB not a recall, no charge and they even washed my car after. It took about half-hour.
 
#33 ·
Below is a link to my post concerning the SSPC5 Update that was done (along with SSPC4, Bose speaker issue). On of the three things addressed concerns battery drain.