2016~2023 Battery drain in 2020 Mazdas

I bought my 2020 CX9 earlier this year (Signature model) and, due to Covid, wasn't driving it much. It took the dealership awhile to assess, but it was the Power Liftgate causing the issue as well. At first they did advise I not leave the car undriven so long (but this, of course, is not acceptable). Since fixing the issue I continue to leave the car for days without driving and I have not had any issues.
 
Alright - happened to me.

2020 CX 9 GT. Last driven on Saturday Oct 10, and I couldn't turn it on today. The lights won't even turn on when I open the door.

Emailed dealership and Mazda Canada.

Has anyone in Ontario, Canada had this issue and gotten it resolved with a PLG control module replacement?
 
It happened to my car (20 XC-9 GT) today. The power lift gate module was replaced as part of the recall few months ago. So I am not sure what is the cause for the battery drain. I thought one of the passengers my have left the doors open.
 
Alright - happened to me.

2020 CX 9 GT. Last driven on Saturday Oct 10, and I couldn't turn it on today. The lights won't even turn on when I open the door.

Emailed dealership and Mazda Canada.

Has anyone in Ontario, Canada had this issue and gotten it resolved with a PLG control module replacement?
Update

Mazda Canada is aware of this issue. Dealership is aware of this issue. Dealership fixed it, free of charge.

If anyone needs the paperwork, let me know.
 
Update

Mazda Canada is aware of this issue. Dealership is aware of this issue. Dealership fixed it, free of charge.

If anyone needs the paperwork, let me know.

Please post the paperwork if possible. It would really help anyone who is having issues getting a resolution from the dealer.

If you'd like, you can send me photos of the paperwork in a private message and I can block out the personal info, then post it here.
 
I've noticed that since COVID hit, and I'm working from home, rarely driving, my starts, especially in cold weather, are a little labored. Wondering if it's worth putting a slow trickle charger on the car for an hour a day when I'm not driving for weeks at a time(?).
 
I've noticed that since COVID hit, and I'm working from home, rarely driving, my starts, especially in cold weather, are a little labored. Wondering if it's worth putting a slow trickle charger on the car for an hour a day when I'm not driving for weeks at a time(?).

Can't hurt to try IMO. My starts are also a little slower these days, so I'll be putting my trickle charger on the car tonight.
 
Subscribing as I am dealing with this issue on my 2020 CX5 Signature. Battery has been dead twice. Both times, car was left unlocked. When it's locked, it doesn't seem to drain the battery. I called my dealer and they have ordered the replacement part.
 
I received a recall notice in the mail today for the PLG module on my CX-9. I expect if you have an impacted vehicle you should be getting the same soon.
 
Mazdas are a very good car. I am driving one for already nine years and I didn't have any serious problems with it. The most serious problem I have was with my battery. I got under rain and the battery got in the engine zone where is the battery. It wasn't charging so I decided to recondition it. I found a method on batterytools.net. In my opinion, it was way more affordable than buying a new one. It worked and it started to charge, but the main disadvantage is that it doesn't work as a brand new battery, but at least it is good enough to engine my car.
 
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I take each of my cars out for a highway run that is about 12-14 miles total distance, every week but never exceeding every 2 weeks. I may even stop to do something else, like dropping off used oil at the auto parts store or stopping by the ATM, Walmart, etc.
This way, my car batteries are always fully charged and ready. If you let the battery charge get down to a level when starting is a bit labored then the life of the battery may already be shortened.
 
I take each of my cars out for a highway run that is about 12-14 miles total distance, every week but never exceeding every 2 weeks. I may even stop to do something else, like dropping off used oil at the auto parts store or stopping by the ATM, Walmart, etc.
This way, my car batteries are always fully charged and ready. If you let the battery charge get down to a level when starting is a bit labored then the life of the battery may already be shortened.

Understood. But this isn't just letting the car sit and never working the battery. The issue is a bad part that drains the battery. There has been a recall from Mazda to address it that I think others have mentioned.
 
The issue is a bad part that drains the battery.
Exactly.
If your battery is healthy and your vehicle is healthy, then there shouldn't be a problem letting it sit for a week or two. People leave their cars at airports all the time, and most of them start up again no problem after a week or two of sitting. I've done it with no problems.
If your battery goes dead over a period of 3-4 days, then there's a problem. That is not normal.
As an example, my 6 gets parked in an unheated garage for weeks at a time during a bad spell in the middle of winter weather. Starts every time.
 
Understood. But this isn't just letting the car sit and never working the battery. The issue is a bad part that drains the battery. There has been a recall from Mazda to address it that I think others have mentioned.
I forgot to include a quote from BRnPA when he posted this:
"I've noticed that since COVID hit, and I'm working from home, rarely driving, my starts, especially in cold weather, are a little labored. Wondering if it's worth putting a slow trickle charger on the car for an hour a day when I'm not driving for weeks at a time(?)."

This is what I was replying to.
 
I forgot to include a quote from BRnPA when he posted this:
"I've noticed that since COVID hit, and I'm working from home, rarely driving, my starts, especially in cold weather, are a little labored. Wondering if it's worth putting a slow trickle charger on the car for an hour a day when I'm not driving for weeks at a time(?)."

This is what I was replying to.

Gotcha. Makes sense. Thanks for the clarification. Have a great weekend!
 
Having issues with possible battery drain on my 2020 "Mazderati" (that's what I call her :) ) CX-9 GT. I bought it brand new in late Oct 2020 from the Mazda dealership in Huntsville, Alabama. Two months later, (over NY weekend and while out of town, no less), went to get in it and it was dead as a doornail. We chalked it up to bad luck on a battery and got a new one at OReilly's. Today, I went to get in it and it was dead as a doornail. Not even a jumpbox would fire it up; my husband had to use his car. Once started, we left it running for about 15 minutes. We thought that because it had sat for a week without being driven, and because we've had a sudden and prolonged cold snap, that the battery was just drained. Well, two hours later, I went to start the car and it was dead. The battery was still within the warranty period, so we drove (she was struggling to get there, all my sensors were malfunctioning and she never made it to 2 RPMs) to get it tested and replaced. Unfortunately OReilly's battery tester was broken so we got it replaced without testing it. I talked to the dealership and they replaced the rear power lift gate prior to them selling me the SUV, so that's not the issue.
 
Maybe not your case, but i once left the car in an « on » state after parking the vehicle. I got distracted and pressed the push button start to stop the car before putting the car in park (still in drive). When you do that the engine turns off but the car stays on. Put it in park after pressing the push button and walk away with the car still on. I came back to a dead battery.

If you want to confirm if you have a parasitic draw that is draining the battery and that it is not human error, there is a procedure in the TSB to confirm the draw.
Post in thread 'Battery drain in 2020 Mazdas'
https://mazdas247.com/forum/t/battery-drain-in-2020-mazdas.123872557/post-6694492
 
Having issues with possible battery drain on my 2020 "Mazderati" (that's what I call her :) ) CX-9 GT. I bought it brand new in late Oct 2020 from the Mazda dealership in Huntsville, Alabama. Two months later, (over NY weekend and while out of town, no less), went to get in it and it was dead as a doornail. We chalked it up to bad luck on a battery and got a new one at OReilly's. Today, I went to get in it and it was dead as a doornail. Not even a jumpbox would fire it up; my husband had to use his car. Once started, we left it running for about 15 minutes. We thought that because it had sat for a week without being driven, and because we've had a sudden and prolonged cold snap, that the battery was just drained. Well, two hours later, I went to start the car and it was dead. The battery was still within the warranty period, so we drove (she was struggling to get there, all my sensors were malfunctioning and she never made it to 2 RPMs) to get it tested and replaced. Unfortunately OReilly's battery tester was broken so we got it replaced without testing it. I talked to the dealership and they replaced the rear power lift gate prior to them selling me the SUV, so that's not the issue.
In order to fully charge your battery in a timely manner, you must use a battery charger. It is handy to have one at home. If I have time, I'll leave the charger at 2 amps for at least 24 hours. Otherwise, the 10-amp setting should charge the battery fully within a few hours, depending upon the battery's state of discharge. But simply starting the car and letting it idle is not going to do much good. Driving the car on the highway for a few hours would work but then you are burning fuel that is not inexpensive.
 
Took the SUV to the dealership in late November for a 4 day parasitic draw test. They found no issues. They did tell me the battery I put in it was a little too small. So I decided to take my chances and drive ad long as I can because the battery shop won't allow me to pay the differential to upgrade the battery.

Well, that lasted barely 2 months. Car is dead again. Going to have to put the right size in it. Maybe that will fix it. But it still doesn't explain why the battery that same with the car crapped out in two months. Four batteries in two years.

I have a bad feeling I'm stuck with a lemon, as this seems to be a chronic issue with this brand. Very disappointing and I'll be sure to avoid Mazda in the future.
 
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I would've asked the service manager to record the current draw to the battery. Here's a test procedure for an older CX5 with 2-liter engine, just to give an idea as to what the dealership should've done.

1. Verify that the ignition is switched off (lock) and all doors, the hood and the trunk/liftgate are closed.

2. If using a series-type ammeter, continue to Step 3. If using the GR8-1291 Battery Maintenance Station with the inductive amp clamp, skip to Step 6.

3. Disconnect the negative battery cable..

CAUTION:



  • Operating electrical loads while the parasitic draw is being measured can damage a series-type ammeter.
4. Connect the meter between the negative battery terminal and negative battery cable. Proceed to Step 10.

5. Select the DMM icon from the main menu.

6. Select the DC Ammeter.

7. Select the 70 AMP MAX range. (measuring milliamps)

8. Connect the amp clamp to the negative battery cable.

9. Monitor the current draw.

NOTE:



  • If the battery is not left undisturbed for 10 min or more, but less than 2.5 hours
    , the tester will indicate a high value (approx. 200 mA
    ).
  • If the ignition or any electrical accessory is operated after the tester is connected, the battery must be left undisturbed for 10 min or more, but less than 2.5 hours
    from that point.
  • For vehicles with the immobilizer system, the system periodically shifts synchronization of the security indicator light flashing. Therefore, 65 mA (0.1 s)
    current draw is supplied when the security indicator light is illuminated, and 40 mA (2 s)
    current draw is supplied when the security indicator light is not illuminated. In addition, the measuring instrument, which shows the average value, indicates around 55 mA
    .
10. Leave the vehicle electrical system undisturbed for 10 min or more, but less than 2.5 hours

, and then measure the parasitic draw.

  • If not within specification, measure the parasitic draw while removing the fuses one by one from the inside of the main fuse block and the inside of the fuse block.
  • Inspect and repair wiring harnesses and connectors of the fuse where the current draw has decreased.
  • Parasitic draw (When the ignition is off (lock), all doors and the hood are closed.)

  • 40—65 mA
NOTE:



  • If the battery is left for 2.5 hours or more
    , a battery parasitic draw value of 25—45 mA
    is indicated.
 
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