Hello everyone! So last night I left the car in accessory mode. Come out in the morning and I'm like damn. I started the car then I got a solid battery light on dash, infocenter was telling me charging system malfunction. From my understanding the voltage system is to low. It barely runs and when u cleared codes came back. Battery now dead from idling trying to figure this out. Any way to pin point since I left the car on accessory overnight and started it and now I'm getting the code and having this issue. Could it be the fuse on the positive terminal?
P2503-00
- Thread starter Xitztyler
- Start date
Yeah I went to autozone and they fully charged the battery. Dim lights power windows weak, I made it to my house and idled in the driveway while making a post here and the car stalled out.
I know the battery could be shot from draining from it so much and so low?
Was the charging light lit (meaning alternator not charging). I'm surprised it would stall if it's charging even with a bad battery. The alternator should supply enough to keep it running. It looks like you might need a new battery and need to have the charging system checked. How old is the battery? Did Autozone check to see if the system is charging and did they load test the battery? If the system isn't charging then the battery , even if good will be depleted by driving around or even just running plus any lights or A/C etc that is also taking power. Unless something more serious is wrong, this shouldn't be difficult to fix.
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Second that. Once it's running, it should be able to continue running on just the alternator.
To the OP: This is a crude test, but If you can somehow get it started again, put a voltmeter on the battery terminals while it's running. It should read about 14.5 volts. If it's still below 12 volts, more than likely there's a problem with your charging system. May be nothing more than a blown fuse.
Good luck
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- South Carolina
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- 12 MZ5 13 CX-5
Mazdas tend to be super picky about a dying battery. Even if the alternator is fine, if the battery is low, it can cause all kinds of weirdness to happen. You'd think the alternator by itself could handle it, but with the way the PCM and BCM interacts with the charging system, this isn't exactly true.
I've been buying my Everstart MAXX batteries from Walmart because they are (relatively) inexpensive and have a 3 year no questions asked warranty. And besides, Walmarts are everywhere!
I've been buying my Everstart MAXX batteries from Walmart because they are (relatively) inexpensive and have a 3 year no questions asked warranty. And besides, Walmarts are everywhere!
So I brought battery to interstate battery to warrenty out and the battery dead is reading 12.7 volts. He said to charge it and bring it back to do further testing to see if it is the battery, so the battery is at autozone for 45 minutes to charge, then I'll bring it back to interstate see what guy says.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
"warranty out the battery"? What does this mean? If your CX is a 2016 then your warranty is long gone. Did you buy a new battery at some point?
Also, how long was the battery on a charger? 45 minutes is NOT long enough to fully charge a depleted battery.
Also, how long was the battery on a charger? 45 minutes is NOT long enough to fully charge a depleted battery.
Yes I bought a new battery at some point, but the battery has no issues the guy said. I went to my local salvage today and got a used alternator, I'll keep you guys posted! Thanks everyone!
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
You bought a used alternator? Did you test the old alternator?
A simple test, if you have a voltmeter, is to check the voltage at the battery before starting the car. It should read in the vicinity of ~12.5v.
I just now checked the battery in my 2016.5 CX and it's a bit low at 12.2v. This is the original battery so it may be time to change mine out in the near future.
Now start the car and check the voltage at the battery. After a couple of minutes, it should jump to around ~14v. If it doesn't jump up, then your alternator is suspect.
A simple test, if you have a voltmeter, is to check the voltage at the battery before starting the car. It should read in the vicinity of ~12.5v.
I just now checked the battery in my 2016.5 CX and it's a bit low at 12.2v. This is the original battery so it may be time to change mine out in the near future.
Now start the car and check the voltage at the battery. After a couple of minutes, it should jump to around ~14v. If it doesn't jump up, then your alternator is suspect.
I suggested doing the same quick test in my post a few days ago, but seems to have been ignored. It's a quick test and although it may not be definitive, at least it's a start.
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
Sorry, I missed your post on this.
Car batteries really don't take being "deep cycled" very well. The battery doesn't discharge all that much when starting the car (think a few percent). What you did by leaving the car in accessory mode likely discharged it much more. On an old car battery, this can be terminal. Even brand new car batteries don't really handle this all that well, which is why "deep cycle" batteries exist.
My battery died during the pandemic, probably due to the car sitting for months unused. I hooked it to a battery charger/tender and charged it, but it wouldn't hold a charge for more than a couple days. When I took it to the store, the AutoZone tester said it was fine. As was mentioned previously, Mazda's can do weird things when the battery is on its way out. My dashboard was lit up like a Christmas tree. I ended up buying a battery at Walmart, swapped it in, and all was well.
Personally, if the battery is more than a couple years old, I'd just go buy a battery at Walmart and see if it fixes your issues before swapping alternators. The warranty on the current battery is probably pro-rated so you really aren't getting a free battery anyway and at some point your time is more valuable.
My battery died during the pandemic, probably due to the car sitting for months unused. I hooked it to a battery charger/tender and charged it, but it wouldn't hold a charge for more than a couple days. When I took it to the store, the AutoZone tester said it was fine. As was mentioned previously, Mazda's can do weird things when the battery is on its way out. My dashboard was lit up like a Christmas tree. I ended up buying a battery at Walmart, swapped it in, and all was well.
Personally, if the battery is more than a couple years old, I'd just go buy a battery at Walmart and see if it fixes your issues before swapping alternators. The warranty on the current battery is probably pro-rated so you really aren't getting a free battery anyway and at some point your time is more valuable.
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- 2014 & 2019 CX-5 Touring(s)
You can get a cheap voltmeter for under $10 at Amazon/Walmart/Harbor Freight. Lot cheaper than a used alternator. And cheaper than replacing an alternator unnecessarily.
I really think it's the battery I'm already half way done with alternator, ughh, when the guy told me the battery was good, I should've known it was the battery damn
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- 2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
So, without any testing at all you decided to swap out the alternator?
Ok then...
Ok then...
