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

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.

Yes, I direct-mounted it under the hood using the o-rings it came with. Earlier in the thread someone else had suggested not getting a 'dedicated' direct-mount one like this, and instead getting one with alligator clamps that could easily be moved from vehicle to vehicle. I can certainly appreciate why that option might be attractive to some, but for me it made total sense to get the direct-mount one and install it under the hood. I got it all rigged up so that just the male end sticks out of the front of my vehicle. So i can go and plug it in without even needing to lift the hood at all, which is super convenient. I saw that NOCO even makes flush-mount ports you can install on an exterior surface of your vehicle with a weatherproof cover/cap. With those you just open the cover and plug your extension cord into it. I really like that, too, but it looks like you have to use a 2 inch hole saw to cut a 2 inch hole in your vehicle to install it. I'm not overly comfortable doing that myself at this point.

So far I've been using the charger on days when I'm not driving my vehicle and have had no issues, of course. I also bought myself a DC clamp meter and have been monitoring the draw a bit (when not plugged into the charger, of course). With the doors locked, the draw seems to fluctuate between about .08 amps and .20 amps, depending on how I position the meter. It seems to be quite sensitive, and I'm honestly not sure how accurate it is. I paid less than $40 for it from Amazon, just so I had something to try to continue monitoring this with. Looks like you can spend hundreds (literally) of dollars on them, but I wasn't about to do that.
 
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Northeast
:
2020 CX-5 Tour
.... I also bought myself a DC clamp meter and have been monitoring the draw a bit (when not plugged into the charger, of course). With the doors locked, the draw seems to fluctuate between about .08 amps and .20 amps, depending on how I position the meter. It seems to be quite sensitive, and I'm honestly not sure how accurate it is. ....

Have you also checked the draw when the vehicle is unlocked? And how long are you waiting to test, after closing the door, locking/unlocking, ect.

Clamp meters are very sensitive to position and movement (my inexpensive unit is anyway), so it's important to be as motionless as possible when using them. Also, you'll probably get more fluctuation and less accuracy if your '16 has 2 separate ground wires (body and engine) branching off from the battery connector, and you've clamped around both wires at the same time. If that's what you're doing, then try comparing the 2-wire single reading to the sum of the 2 wires clamped separately.
 
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Pueblo county CO
:
CX-5 Sport 16.5 6M
Yes, I direct-mounted it under the hood using the o-rings it came with.
I thought about that but I wasn't sure where to mount it.

So you have the 110v plug sticking out of the grill? That should be a convenient location. Do you have any pics for your installation?
 
Have you also checked the draw when the vehicle is unlocked? And how long are you waiting to test, after closing the door, locking/unlocking, ect.

Clamp meters are very sensitive to position and movement (my inexpensive unit is anyway), so it's important to be as motionless as possible when using them. Also, you'll probably get more fluctuation and less accuracy if your '16 has 2 separate ground wires (body and engine) branching off from the battery connector, and you've clamped around both wires at the same time. If that's what you're doing, then try comparing the 2-wire single reading to the sum of the 2 wires clamped separately.

Yes, i've checked with the the vehicle both locked and unlocked.

For doing it locked, I've unlocked the car first to pop the hood. Once popped, I lock it and then attach my clamp meter. Initially the draw shows somewhere around 1.4 amps, but as it sits there and things turn off/shut down it drops to a low of around .08 amps or so, as I mentioned earlier. I've let the meter sit on it for up to about 20 minutes, occasionally taking it off to reset it/zero it out, and it doesn't really go any lower than that.

I also tried it unlocked the other day using the same method as described above. Doing it that way it dropped to a slightly lower low of around .05 amps or so, positioning it similar to how I did with the doors locked (again, it seems to be very sensitive based on how you position it).

As for what i'm clamping, i've just been doing the largest of the ground wires branching off from the battery connector. I think mine actually branches into 4, but i'm not getting anything on 3 of the 4; only on the largest one.

As an aside, yesterday I got curious what voltage my wife's car battery would show after it's been sitting in our driveway unstarted for about 4 or 5 days. For reference, it's a 2020 Kia Sportage SUV. That only showed 12.28 volts when I tested it with my meter, which is rather low. It started right up for her without issue, though. In fact, she's never had any issues with hers starting, and she drives it no more than I do mine at current. I guess I found it interesting that the voltage on hers was that low, with no suspicion of there being a possible parasitic draw as with my Mazda. This makes me wonder more if the lack of driving is the issue here.
 
I thought about that but I wasn't sure where to mount it.

So you have the 110v plug sticking out of the grill? That should be a convenient location. Do you have any pics for your installation?

I really wanted to route the 110v plug such that it stuck out of my grill, but I couldn't find a spot big enough to fish the head of the plug through to get it so it stuck out of my grill. So I had to do something a little different. I don't love the plug just kind of dangling there, but its working for now, and not terribly unsightly. One of the NOCO flush-mount ports I previously mentioned would be the ultimate solution here. I'm really not up for cutting a 2 inch hole in my car though, to install it.

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Northeast
:
2020 CX-5 Tour
... This makes me wonder more if the lack of driving is the issue here.
As others have already posted previously, a healthy battery should not be significantly affected by inactivity for a few days, as long as the continuous draw is not above .03A. So it would appear that the .05A your seeing might be the underlying cause (and .08 certainly would be).

However, before making that definitive call, I'll ask if you've checked the draw with your clamp meter multiple times a few hours after shutting down? As you have discovered, these inexpensive clamp meters are really quirky, and I've found that mine often gives bogus readings, depending on a number of factors. However, I've also compared the clamp meter reading to the amp reading from another meter in series, and the results are an exact match, once the clamp meter 'settles down' (the best way I can describe it).

So I always do the clamp meter reading multiple times, zeroing and re-clamping each time, trying to keep the meter as perpendicular and as quiet as possible. After a few tries, I usually start seeing a consistent result, and take that as being accurate.

So if you can confirm those .05 and .08 amp results over multiple tries with your clamp meter, then I believe you've confirmed a small parasitic draw - enough to eventually kill any battery. And at that point you can also start pulling fuses, as you described in your OP, in order to try to identify which circuit group is the culprit. You'll need to find a good prop to hold the meter solidly clamped in place while you pull fuses. And accessing the cabin fuses would require manually jamming the door switch closed well in advance of the testing, in order to get valid results.
 
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Pueblo county CO
:
CX-5 Sport 16.5 6M
I really wanted to route the 110v plug such that it stuck out of my grill, but I couldn't find a spot big enough to fish the head of the plug through to get it so it stuck out of my grill. So I had to do something a little different. I don't love the plug just kind of dangling there, but its working for now, and not terribly unsightly. One of the NOCO flush-mount ports I previously mentioned would be the ultimate solution here. I'm really not up for cutting a 2 inch hole in my car though, to install it.

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I guess if the plug doesn't flop around and bang up the paint on the highway. I always carefully try out my modifications and check things for problems.

They have all kinds of cables and mounts on Amazon. I ran a cable into the cabin but I had to remove the battery for access.

I thought about trying to run a cable to someplace on the bumper, but there are other things under there. A lot of trouble.
And drilling a hole is out for me, too.
 
:
Alberta
:
2018 CX-5 GT
No question the newer cars have bigger power requirements with all the fancy gadgets, shortening the life of the batteries. Think nowadays your lucky to get 3 or 4 yrs. out of a battery. The DC clamp makes things easier, and less disruptive to try and track down a parasitic draw. But you have to be careful not to inadvertently "wake up" a system that might draw to much amperage and blow your meter (depending on brand/setting). From what I've read 25-50 milliamps is the most the car should be drawing.....after the PCM and other systems go to sleep (can take up to an hour) after turning the car off. Each time you open a door, open your hood, or even pull a fuse, systems can be woken and send your amp draw higher. Having the maintainer on should keep the battery from losing to much power, given you aren't apparently driving it enough to keep the battery charged that way.
 
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Pueblo county CO
:
CX-5 Sport 16.5 6M
I have a Scangauge plugged into the Obii port. It always lights up when I start the engine, but it also seems to come to life on its own at times. I have seen it light up for a few seconds then go off.
 
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18 Mazda CX5 AW
For anyone needing a new or replacement battery charger/maintainer
What's the consensus as to what's the best product and value? :

1. Battery tender
2. NOCO
or
3. CTEK ?
 
:
Pueblo county CO
:
CX-5 Sport 16.5 6M
I have a Black & Decker and. Chinese brand oollong or something.

Both of them say they support AGM recharging.
Most of them have smart electronics and desulfating mode.
 
For anyone needing a new or replacement battery charger/maintainer
What's the consensus as to what's the best product and value? :

1. Battery tender
2. NOCO
or
3. CTEK ?

I'm pleased so far with the NOCO Genius 2D I installed. Granted it's only been a few weeks so far. I have no experience with CTEK or other comparable brands. Everything I have read about NOCO seems to be good though, and their prices seem to be fair, comparatively.
 
:
18 Mazda CX5 AW
So usually use regular terminal tester to test battery/ alternator.

While in Harbor freight, happened to see a cheap tester plug in for $6. Was skeptical of it working but would be quick way to check when it's cold out. Doesn't give you a read out , just if within averages.

So plugged in Nissan, no reading. Turned car on to get results which were accurate.

Plugged into mariner suv, have results.of weak battery but good alternator which is accurate.

Plugged into Mazda...also gave accurate results right away.

The tester is great for quick diagnosis until you need actual voltages, etc.

Expected that mazda has slight power drain to keep computer memory.
However, what was troubling is it appears the Mazda cigarette lighter provides power when the car is off. So anything you have plugged in is leaching power. Including most phone cables which have indicator lights on them.

Never gave this a second thought before but will have to make sure cell chargers are pulled during cold winter nights.
 
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:
CX5 GT
that is strange. Mine does turn off the front cig lighter socket when the car is off.
Also for accurate measurement you have to wait about 15 mins. All electronics go to to sleep around that time (if car and ACC is off, door closed as well) and consumption drops to almost idle after that period. Hood can be open and car can be locked at the same time because most of the US models dont have the hood switch (unless remote start oem is fitted)