I'm guessing this would have been covered by the initial GR8 test, but I have no idea. If I get the chance, I'll try and see.
Battery Dead .5~1.0V voltage drop normal?
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I'm guessing this would have been covered by the initial GR8 test, but I have no idea. If I get the chance, I'll try and see.
Moonlighter, you mentioned getting a 10A Victron charger. Do you think https://www.amazon.com/dp/ (commissions earned)be sufficient? (I'm trying to save a few bucks.) Would a 5A simply take longer to charge?
I don't know if it matters but I'm probably going to get the following battery.
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- W WA
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- 2024 CX-5 Premium
Depleting the battery once would not have killed it.
Driving every 2-3 days should not be a problem, even longer should be fine. If it is a problem then there may be something in the car that is depleting the battery, perhaps an accessory like a dash cam that is set up such that it is always drawing power.
I immediately turned off the dashcam's parking mode after it had depleted it once because the same thing had already happened in my CRV.
I've read a lot of posts in this forum where Mazda owners have gone through multiple batteries in a year or two, especially for cars in my year 2023.
I'm wondering if the keyless fob has anything to do with this. Mine doesn't work well. About a third of the time, my doors won't lock. And I just read a post where the battery drains whenever the door remains unlocked. So I'm wondering if this has been killing the battery.
If this is such a problem, I'm kinda' mad at the dealership for not mentioning this. Maybe, they are trying to push all of the blame onto the body shop owner because they know that Mazda isn't going to pay for this.
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- W WA
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- 2024 CX-5 Premium
I've had 2 CX5s, a 2020 and currently a 2024. Both had dash cams, both were kept unlocked at home, neither one had any problems with the battery.
If not on a switched circuit your dashcam will be consuming power even though you've disabled parking mode. I would disconnect the dashcam until you've resolved the problem with the battery, just to eliminate one potential cause of the problem.
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- 2024 CX5 Akera G25
5A is good for keeping a well charged battery topped off. But not for charging up a depleted battery. It would probably overheat and cut off.
Best to get at least 10A or better still 15-20A. I have both a 5A CTEK that I use to keep by boat’s batteries topped off, and a 20A Victron for times when I have to charge up a low battery.
IMO the 2 best battery charger brands, by a mile, are Victron and Ctek. I know that Americans love their NOCO’s but IMO they’re not in the same class as those two. See too many NOCO’s failing for my liking.
Do you not have a battery or auto parts shop near you that will test the battery for you?? Most do it for free or a small charge. And BTW I have seen battery testers give false readings more than once….. but anyway, you have one of three things going on IMO
- bad battery (most likely)
- alternator not charging properly (next most likely)
- a parasitic drain somewhere (possible but least likely)
A good auto electrician will diagnose this in 10 minutes.
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- Mazda CX 5 Touring
A parasitic draw test needs to be done!
HyFlyer
2019 CX5 sig 2.2 diesel / 2016.5 CX5 touring 2.5na
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- Southwest Ohio
Also, have you checked the electrolyte level in the six cells of your battery? Unless something has changed, every Mazda I've owned you have to occasionally top up the electrolyte in the battery with distilled water. They are NOT "maintenance free".
@Moonlighter - I can’t speak for automotive Victron products but in solar arena (US Market) the brand now gives me pause from consideration with failures (forums) in recent years… it seems to no longer be a “sure thing” and reliable brand
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
While I agree that the 10amp charger is what's needed here. I don't agree that a 5amp charger attached to a completely discharged battery is going to overheat. Perhaps years ago, but not these days with any halfway decent modern charger. The charger will limit its output to keep from trying to source more than it can provide.
Is there a brand you'd recommend?
Interesting info about how dashcams draw power even without parking mode.
I did disconnect the dashcam to eliminate one possible variable and the battery was still dying.
There are auto part stores nearby but the car is currently at the body shop. Is the equipment at the auto parts store different than the GR8 at the dealership?
I'm wondering if it's just easier to just replace the battery. But I guess doing an additional test can't hurt.
I'm going to do this. This would eliminate the possibility that the body shop screwed up. Would a parasitic draw test determine a loose ground wire?
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- 2024 CX5 Akera G25
The purpose of a second battery test is the same as getting a second opinion from a Dr. - because the first test may have been wrong! As I mentioned, I have seen professional level battery testers give false results on more than one occasion. Mazda’s tool is likely no different. A second, independent test will either verify their results, or not.
As far as Victron auto battery chargers are concerned, you cant equate their performance to solar controllers. Their auto battery chargers have been the industry standard for decades. Them and CTEK.
The best professional to diagnose this issue is an auto electrician. Not a car body shop, unless they have an auto electrician on staff or get one in.
As far as Victron auto battery chargers are concerned, you cant equate their performance to solar controllers. Their auto battery chargers have been the industry standard for decades. Them and CTEK.
The best professional to diagnose this issue is an auto electrician. Not a car body shop, unless they have an auto electrician on staff or get one in.
I went to another guy and he's also thinking that it might be a battery issue. He doesn't think it's a ground because the symptoms don't match up. He did perform his own battery test but it came up with weird results. The battery wasn't fully charged though. The test stated that the alternator was faulty.
I'm probably just going to replace the battery and see what happens. I'd like to thank you and everyone else here for the help. Really helped.
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- W WA
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- 2024 CX-5 Premium
Is there a reason that you discounted his diagnosis of faulty alternator?
You have received good advice but it seems to me you haven't paid much attention to it as you still have no confirmation of whether or not the battery you have is good. You can just replace the battery but if the problem lies in the charging system or a parasitic draw you may be wasting your time and money.
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- CX-5 Sport 16.5 6M
This could be the problem, and even a new off-the-shelf battery can be run down from just sitting. A good battery shop will fully charge the new battery before it's installed.
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- 2024 CX5 Akera G25
Absolutely! I have found that new batteries are rarely fully charged when installed.
The last two new batteries I have had installed needed to be charged up even after I had driven 40 minutes to get home after they were installed. One took a further 3 hours on my 20A charger to get fully charged.
But as they say, on how this thread has gone ….
“you can lead a horse to water, but you can’t make it drink”.
I don't know much about cars. It was the guy who said the alternator is probably fine. He inspected the copper coils and stated there wasn't any discoloration, which usually indicates a faulty alternator. He also said that since this is a new car (1 year), it's probably not the alternator. I'm just going by what he said.
I actually just did a parasitic draw test. The multimeter actually showed 5.00 amps (not milliamps) are being drawn) while I have everything inside the car turned off. It seems that this is the issue. I guess it's not the battery?
Any ideas what would be causing the parasitic draw in a newish CX-5?
I didn't get the chance to start pulling fuses because I accidentally blew my multimeter by touching the positive and negative terminals together with the multimeter. I have to go to Home Depot and go pick up another multimeter…
With that kind of draw, you should be able to find the problem by touching relays with your hand.
Maybe I misread my multimeter and it was 5 milliamps? But then wouldn't 5 milliamps be a bit too low?
I don't get it because wouldn't 5 amps drain the battery overnight? (I was able to start the battery this morning.)
I burned my multimeter so there is no way to recheck it until I get to buy a new one. I'll let you know.
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- W WA
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- 2024 CX-5 Premium
Your multimeter has a fuse, to prevent being destroyed from situations of too much current, just need to replace the fuse with one of the correct rating. It may have come with a spare fuse.
I suggest taking your car to a professional, you are in over your head troubleshooting this yourself.
