Parasitic battery drain on 2016 Mazda CX-5 Sport. Looking for help

This new class of SMART chargers are claimed to be able to rejuvenate a sulfated, undercharged and abused battery. NOCO is good brand. I have a small B&D branded one, plus a larger (8amp) "asian" one.

I think most battery failures are either:
1) old age/sulfation/undercharged or
2) heat damage/warped plates.

I also have 16.5 Sport. It wouldn't start and was rundown. I replaced the OEM Panasonic a couple of years ago with a Redtop Optima, for heat resistance ( I live in a hot climate).

I moved the Panasonic to my other car. That car charges the battery a little 'harder', usually at ~15v ! The battery still works. I do try to plug in the charger several times a month, but it always starts.

The Redtop runs down but😞 I keep a lighter jack voltmeter pluggged in so when it gets down to 12.3-12.4v I charge it. The voltmeter is of course a parasitic drain in itself .....

Otherwise, I'm not sure if I have parasitic drain in the cx5 or nor. Surely not 1.7a, but usually a few days and the voltage is 12.4v which was at 12.8-9v after a drive.
It doesn't run down if I disconnect it.

Yyrwei52 is right, you should monitor the voltage and find the parasitic drain. But a SMART charger/tender will help keep you on the road.

The battery has the 5-year warranty, but I'm guessing your cx5 is out of warranty. Still, if there is a TSB or something that 'fixes' it, maybe Mazda will help.
 
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Even if you want (or need) a battery maintainer / trickle charger, buy one which can plug in the round cigarette lighter socket so that you can easily use it on any car, not this type which is “dedicated” to one vehicle.
Both of the ones I bought from Amazon have SAE plugs with three attachments: cig plug, alligator clips, o-rings.

I rigged an extra long one with o-rings thru the dash ( also from amazon) so I can plug it in without lifting the hood.
 
> Either the battery can’t hold the voltage (due to internal short), or there’s a significant current draw somewhere else.

One way to find out is, disconnect the battery after engine shut off.
Measure voltage after 0 mins, 20 mins, 40 mins, etc.
The voltage should not drop too much.
If it does, you know there is an internal current leak.
If not, the problem is external... something is draining the battery.
Do you have any device plugged into the 12V socket inside the center console?
Just a guess.

No, I don't have anything plugged into the 12V socket inside the center console at the moment. Nor have I for some time now.

I had the battery tested yesterday at the battery shop where I purchased it. It failed a load-test, but it was also only 53% charged at the time. They agreed to keep the battery, charge it up to full, and then re-perform a load-test on the fully charged battery. They said that should give a more accurate result of whether the battery is faulty or not.
 
⋯ Now this’s the best opportunity for you to compare. Check the voltage to loaner battery like before and see if the battery shows the same voltage drop.
Better yet, check the current of parasitic drain by removing the negative terminal of the loaner battery like you did before to your own battery and see if it’s still 1.7A.
 
As I said before, we don’t drive our CX-5 much, sometimes once a month, and our battery has no issue to start up without a battery maintainer.

Now this’s the best opportunity for you to compare. Check the voltage to loaner battery like before and see if the battery shows the same voltage drop.

+1 to all of this from yrwei52, and also the owner is correct about the battery needing to be charged before the load test. However, the possibility of a bad battery cannot be eliminated even if the load test comes back ok, because I've read multiple reports of batteries being bad despite passing a load test. Apparently the testing tools are not able to catch every type of battery problem, so if his machine indicates a good battery, you should try another shop that uses a different brand of tester. But based on the rapid voltage drops you posted, I'm expecting the load test to fail.

Assuming you do get a replacement battery, I recommend repeating the parasitic draw test - this time adding a waiting period to allow the computers to go into quiet mode. It certainly is possible that your vehicle does have an issue that's ultimately killing the battery by drawing it down repeatedly over time. Such an issue would eventually kill most standard batteries, if it's happening continuously.
 
As I said before, we don’t drive our CX-5 much, sometimes once a month, and our battery has no issue to start up without a battery maintainer.

Now this’s the best opportunity for you to compare. Check the voltage to loaner battery like before and see if the battery shows the same voltage drop.

As the guy at the battery shop was telling me that he thinks this is mainly due to my current driving habits, I specifically recalled your earlier post where you said you only drive yours once a month sometimes and have no issues. I wasn't going to get into with him about why I seem to be having this problem whereas others with the same vehicle seem to have no issues at similar or less driving frequencies, though.

I'd like to think that two same or similar vehicles would behave similar in this regard, with all else equal. Perhaps there are other factors that can come into play though, to explain why one vehicle may experience this issue and another may not? I'm not sure.

Good thought on checking the voltage on the loaner battery. I can give that a try.
 
I'd like to think that two same or similar vehicles would behave similar in this regard, with all else equal. Perhaps there are other factors that can come into play though, to explain why one vehicle may experience this issue and another may not? I'm not sure.

Good thought on checking the voltage on the loaner battery. I can give that a try.

Some models of cx5 have certain options with known issues (the power liftgate).

Mine has an aftermarket XMradio 😒
 
An update to all who have contributed to this discussion here (which I really appreciate, by the way)...

I hadn't heard back from the battery shop as of Tuesday morning, so I gave them a call. They said they charged the battery up and it was holding a good charge for them, so I could come get it re-installed in my vehicle.

When I got there I asked if they re-performed a load-test on the fully charged battery. They said they did and it passed just fine. Apparently they did this before I came, so i didn't get to witness the load-test myself, unfortunately. I will take their word for it, though.

So the guy put the battery back in my car, had me start it up, and it turned right over, of course. I then asked the guy if he had a DC clamp meter he could test for a parasitic draw with for me. He agreed to do this for me, and the results were interesting.

When he first clamped the negative cable it was showing around 1.4 amps of loss, I believe. This was with my key fob sitting in the car and the car unlocked, of course. I then grabbed my fob out of the car and locked it. Almost immediately the loss dropped significantly. I don't recall exactly what to at this point, unfortunately, but relatively low. We proceeded to let the DC clamp meter sit there for a few minutes, after which the loss dropped to between .01 and .02 amps. The guy was not at all concerned with this, and nor was I, really. I think that those numbers are quite acceptable, based on what I've read.

I ended up purchasing a NOCO genius 2D battery charger/maintainer from them anyhow (the one I linked earlier in this thread), given their price on it was actually better than Amazon. And I have since installed it myself, since there's nothing to it. My plan is to utilize this when I will not be driving my vehicle for a few days at a time, just to keep the battery charged up.

As I previously mentioned, I have a bit of a difficult time accepting this is the solution here, but I don't know what else gives at this point; especially given the low draw we were seeing when using the DC clamp meter at the battery shop (which i'm thinking is more accurate than the harbor freight multimeter I was using in series when i previously registered the 1.7 amp draw). I believe my doors were also unlocked when i registered that 1.7 amp previously too, and like I said, when I locked them it seemed to drop rapidly.

Overall I'm left feeling unsettled still, but also not knowing what else to do at this point.
 
An update to all who have contributed to this discussion here (which I really appreciate, by the way)...

I hadn't heard back from the battery shop as of Tuesday morning, so I gave them a call. They said they charged the battery up and it was holding a good charge for them, so I could come get it re-installed in my vehicle.

When I got there I asked if they re-performed a load-test on the fully charged battery. They said they did and it passed just fine. Apparently they did this before I came, so i didn't get to witness the load-test myself, unfortunately. I will take their word for it, though.

So the guy put the battery back in my car, had me start it up, and it turned right over, of course. I then asked the guy if he had a DC clamp meter he could test for a parasitic draw with for me. He agreed to do this for me, and the results were interesting.

When he first clamped the negative cable it was showing around 1.4 amps of loss, I believe. This was with my key fob sitting in the car and the car unlocked, of course. I then grabbed my fob out of the car and locked it. Almost immediately the loss dropped significantly. I don't recall exactly what to at this point, unfortunately, but relatively low. We proceeded to let the DC clamp meter sit there for a few minutes, after which the loss dropped to between .01 and .02 amps. The guy was not at all concerned with this, and nor was I, really. I think that those numbers are quite acceptable, based on what I've read.

I ended up purchasing a NOCO genius 2D battery charger/maintainer from them anyhow (the one I linked earlier in this thread), given their price on it was actually better than Amazon. And I have since installed it myself, since there's nothing to it. My plan is to utilize this when I will not be driving my vehicle for a few days at a time, just to keep the battery charged up.

As I previously mentioned, I have a bit of a difficult time accepting this is the solution here, but I don't know what else gives at this point; especially given the low draw we were seeing when using the DC clamp meter at the battery shop (which i'm thinking is more accurate than the harbor freight multimeter I was using in series when i previously registered the 1.7 amp draw). I believe my doors were also unlocked when i registered that 1.7 amp previously too, and like I said, when I locked them it seemed to drop rapidly.

Overall I'm left feeling unsettled still, but also not knowing what else to do at this point.
Three things:

1. Read somewhere else that even if keyfob is in house that if was closer than 25 feet could/might drain battery. Some suggestions include wrapping keyfob in aluminum foil. Check the forum and other websites for more info. That could possibly be draining your battery.

2 & 3. The store tested and guaranteed you that the battery was good. That aside, you failed to mention if the car sat in cold northern weather, and whether when started you only took short drives or long drives. Most likely the car was sitting too long, and only starting rarely with short drives, especially in cold weather could deplete and possibly kill a new battery.

As you car gets older, not driving it much could eventually lock up your alternator as well. Not to mention brake calipers, etc.

Cars are like people... They need to move. It sounds as if you work from home so your cars not getting it's exercise. You might do some of these already but instead of leaving it parked, some options include, drive and pickup takeout food instead of having delivered, go to the store instead of online shop, take a spin for an hour and let it loose, take a road trip.

Hopefully the keyfob isn't draining your battery and the battery maintainer (along with driving it more) solves your issues.
 
....
Overall I'm left feeling unsettled still, but also not knowing what else to do at this point.
You can do more testing. Try monitoring the battery hourly or so, with the vehicle unlocked, and then repeat the same test after another drive with it locked. You of course don't want to skew the results by using the charger while this testing is going on.

The voltage drop numbers that you posted previously showed conclusively that something is wrong. The possibilities are a bad battery, a parasitic draw, or perhaps both (the battery trashed by a continuous high draw). You'll feel better once the testing shows what the problem actually is.
 

Overall I'm left feeling unsettled still, but also not knowing what else to do at this point.
Thanks for the update.

I believe you missed a perfect opportunity to compare loaner battery with your own battery. At least you should take several measurements on voltage at different time exactly like you did to your own battery.

Comparison with similar criteria is the best way to figure out whether or not if the car is having problems. Like most people don’t have battery problem like you even if they drive a lot less during the pandemic without using a battery maintainer. When you put in a battery maintainer, you simply mask the battery problem you may have. It’s only a patch job and it never actually resolved your problem.
 
Three things:

1. Read somewhere else that even if keyfob is in house that if was closer than 25 feet could/might drain battery. Some suggestions include wrapping keyfob in aluminum foil. Check the forum and other websites for more info. That could possibly be draining your battery.

2 & 3. The store tested and guaranteed you that the battery was good. That aside, you failed to mention if the car sat in cold northern weather, and whether when started you only took short drives or long drives. Most likely the car was sitting too long, and only starting rarely with short drives, especially in cold weather could deplete and possibly kill a new battery.

As you car gets older, not driving it much could eventually lock up your alternator as well. Not to mention brake calipers, etc.

Cars are like people... They need to move. It sounds as if you work from home so your cars not getting it's exercise. You might do some of these already but instead of leaving it parked, some options include, drive and pickup takeout food instead of having delivered, go to the store instead of online shop, take a spin for an hour and let it loose, take a road trip.

Hopefully the keyfob isn't draining your battery and the battery maintainer (along with driving it more) solves your issues.

Thanks for the information on the fob. When my fob is in my house at night time it's definitely within 25 feet of my vehicle. I've consistently put my keys in the same basket in the same location within my house for several years now though. So i'm not sure why I wouldn't have had battery issues for years now if the fob were the issue. I guess what i'm saying is nothing really changed in terms of the proximity of my fob to my vehicle recently that would trigger this (at least not that i can think of). I did find the drop in amps at the battery shop when I removed my fob from my vehicle and locked it to be rather interesting, nonetheless.

Regarding the weather, yes, I'm located in upstate New York, where it gets quite cold in the winter. We definitely experience sub-zero temperatures in January and February. My current battery was installed in October 2020, and it performed fine all last winter when it was cold. It even performed fine all spring and into the summer. I didn't start experiencing issues with in until sometime in August.

My driving habits from October 2020 to now have remained unchanged - very little driving due to me working from home, and when I do drive I'm mostly taking short trips to the market down the street and what not. I fully acknowledge and agree that my limited use of the vehicle these days probably isn't helping matters any. And as I've mentioned previously, the folks at the battery shop seem to think that my lack of driving is a large part of the issue, too. However, I also have others here telling me that they might only start their vehicles once a month maybe, and they don't have any battery issues. So I don't know what gives. There seem to be vastly differing opinions as to whether the issues are merely the result of lack of use or if there's something more going on.
 
Thanks for the information on the fob. When my fob is in my house at night time it's definitely within 25 feet of my vehicle. I've consistently put my keys in the same basket in the same location within my house for several years now though. So i'm not sure why I wouldn't have had battery issues for years now if the fob were the issue. I guess what i'm saying is nothing really changed in terms of the proximity of my fob to my vehicle recently that would trigger this (at least not that i can think of). I did find the drop in amps at the battery shop when I removed my fob from my vehicle and locked it to be rather interesting, nonetheless.

Regarding the weather, yes, I'm located in upstate New York, where it gets quite cold in the winter. We definitely experience sub-zero temperatures in January and February. My current battery was installed in October 2020, and it performed fine all last winter when it was cold. It even performed fine all spring and into the summer. I didn't start experiencing issues with in until sometime in August.

My driving habits from October 2020 to now have remained unchanged - very little driving due to me working from home, and when I do drive I'm mostly taking short trips to the market down the street and what not. I fully acknowledge and agree that my limited use of the vehicle these days probably isn't helping matters any. And as I've mentioned previously, the folks at the battery shop seem to think that my lack of driving is a large part of the issue, too. However, I also have others here telling me that they might only start their vehicles once a month maybe, and they don't have any battery issues. So I don't know what gives. There seem to be vastly differing opinions as to whether the issues are merely the result of lack of use or if there's something more going on.
Location. Texas is not upstate New York. Plus it sounds like you don't drive your car at all. A 5 minute trip isn't going to recharge anything. The battery maintainer is the best easiest fix for you. No reason to not keep it plugged in all the time, it will help the battery last longer, not just keep it charged. To keep a battery healthy a car needs at least one 20+ minute trip a week at minimum. Listen to the people at your battery shop. This thread has been very interesting to read but feels like spinning tires and getting nowhere. I had the same issue on one of my cars and solved it with a $500 deep cycle specialty battery. But I didn't have a place to plug a maintainer in.
 
For safety reasons, i wouldn’t keep it plugged in all the time if it is parked inside in a small garage. Lead-acid batteries can sometime emit fumes when charging. Smart charger are better than they were at preventing charging problems, but they can still fail.

Depleting a lead acid battery also causes it to deteriorate faster, especially if it happens regularly. It is the good old « memory » effect that we used to have on powertools before they switched to li-ion. The battery may still be good enough to pass load tests, but it may never be as good as it was at holding a charge. Charge it up fully and give it a shot, see how long it works for, but there is a good chance the problem will come back this winter.
 
For safety reasons, i wouldn’t keep it plugged in all the time if it is parked inside in a small garage. Lead-acid batteries can sometime emit fumes when charging. Smart charger are better than they were at preventing charging problems, but they can still fail.

Depleting a lead acid battery also causes it to deteriorate faster, especially if it happens regularly. It is the good old « memory » effect that we used to have on powertools before they switched to li-ion. The battery may still be good enough to pass load tests, but it may never be as good as it was at holding a charge. Charge it up fully and give it a shot, see how long it works for, but there is a good chance the problem will come back this winter.
OP lives in upstate New York. It is winter. That is why the problem happened now. The device is not just a charger, it is a computer designed to maintain and keep batteries healthy. These devices can even fix batteries that were damaged by low charge levels if the damage is on the minor side.
 
⋯ My current battery was installed in October 2020, and it performed fine all last winter when it was cold. It even performed fine all spring and into the summer. I didn't start experiencing issues with in until sometime in August.

My driving habits from October 2020 to now have remained unchanged - very little driving due to me working from home, and when I do drive I'm mostly taking short trips to the market down the street and what not. I fully acknowledge and agree that my limited use of the vehicle these days probably isn't helping matters any.
You just said it. Your driving habit hasn’t changed since the new battery installed a year ago, but the battery is just started having the problem a couple of months ago. This simply indicates the battery performance is deteriorated from new, and can’t hold the charge long.

⋯ And as I've mentioned previously, the folks at the battery shop seem to think that my lack of driving is a large part of the issue, too. However, I also have others here telling me that they might only start their vehicles once a month maybe, and they don't have any battery issues. So I don't know what gives.
You have to remember that even if the poor performance of your current battery is caused by lack of driving, it’s not your fault and you’re not obligated to install an additional equipment to prolong the battery life. Your battery shop is not a national chain like Costco, they’re not going to exchange a battery for you easily under warranty unless the battery is almost totally dead. They encouraged you to install a battery maintainer so that their battery can last as long as it can, even if the battery is way below the specs on performance as the battery maintainer simply masks the battery problem.

⋯ There seem to be vastly differing opinions as to whether the issues are merely the result of lack of use or if there's something more going on.
If you actually took the measurements on voltage with different time frame as edmaz suggested on the loaner battery, you could easily verify the problem by comparing the voltages between the two and you’ll know if it’s caused by parasitic current drain, or by the battery with poor performance.

Ok so here are my results...

- Battery voltage immediately prior to me starting this morning: 11.96 V
- Battery voltage immediately after starting (I had to use a jump pack to start it, of course. Jump pack was removed when I took my reading): 13.92 V
- Battery voltage following about a 40 minute drive, prior to shutting engine off: 13.75 V
- Battery voltage immediately after shutting engine off: 12.34 V
- Battery voltage about 30 minutes after shutting engine off: 12.17 V
- Battery voltage about 60 minutes after shutting engine off: 12.15 V

Not sure exactly what these numbers tell me, but now I'm wondering if my charging system/alternator might be the culprit?

I would certainly appreciate any further suggestions you have for me at this point, given these numbers.
 
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OP lives in upstate New York. It is winter. That is why the problem happened now. The device is not just a charger, it is a computer designed to maintain and keep batteries healthy. These devices can even fix batteries that were damaged by low charge levels if the damage is on the minor side.
??? OP started having battery problem in August, which is not winter.
 
I am in Canada. You are correct, it is getting colder, but it is not even remotely close to be winter. Conditions right now are pretty good for batteries actually, not too hot not too cold and engine are still fairly easy to start. This will all change within a few months.
 
??? OP started having battery problem in August, which is not winter.
OP bought the battery last October, went through a whole winter and barely drove the vehicle and when did start up, only drove down the street and back, not long enough to keep charging the battery back to full.

There's a high probability he/she wore down the battery so far over the winter/spring months that it was dead by time summer rolled around.

OP should go to local mechanic for peace of mind if doesn't trust battery store. More than likely a reputable mechanic will tell OP the same thing.

With OP only starting vehicle once per week for short drives, a parasitic drain would have killed battery in short order.
Starting the engine and barely driving it, along with the fan cooling after car shutting off, is going to drain more power than the parasitic drain.

Not sure how much Mazda devices( fan, clock, alarm, computer memory, etc.) drain while car is shut off, but just like your tv, cable box, computer, etc, all modern home and cars devices have some minuscule drain even when turned off.

OP could end up spending a lot of time and money for a problem that isn't there.

Alternatively he/she could put a 48 lb full river battery with 750cca and 64 amp-hours in vehicle which might last longer under those conditions or use a battery charger/maintainer or drive the car more and for longer runs which would keep the battery, alternator and brake calipers in working condition. More than likely if they are in NY and the car is outside instead of garage kept, they'll be replacing siezed calipers next. Being in the north rust belts, means we have to deal with cold, salt, rust, etc. that destroys frames, kills batteries and corrodes/siezes alternators & brakes if the cars are left sitting.

This is based on having this same experience during the pandemic and experiencing a rusted , corroded siezed alternator and two(2) dead batteries. Never had that happen until now. Even though I knew better, still had let the one older car sit while drove the other one. While spending hours changing out the alternator(located in a very difficult place), reminded myself that it would have been easier to just have driven the car.
 
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I ended up purchasing a NOCO genius 2D battery charger/maintainer from them anyhow (the one I linked earlier in this thread), given their price on it was actually better than Amazon. And I have since installed it myself, since there's nothing to it. My plan is to utilize this when I will not be driving my vehicle for a few days at a time, just to keep the battery charged up.

Did you install it under the hood? I think using o-rings on the battery with the SAE connector is the best.

I think you might find giving the battery a full overnight charge maybe once a month will greatly improve things, unless your higher amperage drain continues.

In the winter you might charge more frequently if you do more short trips with the lights, wipers, and heater on.
 
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