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Fuses won't help. The increased current is a consequence, not the cause. The cause is something that triggers the wake-up of the main modules. Under normal conditions, this would be opening a door, the key fob, or remote start. In my case, some module is sending a wake-up signal. A long-term recording with a CAN logger might help to see which module is the initiator. Here's a graph over 60 hours. Random wake-ups are very difficult to diagnose. I’m planning to continuously record the dashboard on video to see if the screen turns on during these random wake-ups.
I don't know how to handle this problem, or at least, how to get Mazda to acknowledge the problem. This requires a really good engineer who understands exactly how everything works — like an automotive version of Dr. House.
P.S. This plot is uncalibrated, must be multiplied by 1.055.
Last edited by obelix662000; Jul 31, 2025 at 07:17 PM.
Fuses won't help. The increased current is a consequence, not the cause. The cause is something that triggers the wake-up of the main modules. Under normal conditions, this would be opening a door, the key fob, or remote start. In my case, some module is sending a wake-up signal. A long-term recording with a CAN logger might help to see which module is the initiator. Here's a graph over 60 hours. Random wake-ups are very difficult to diagnose. I’m planning to continuously record the dashboard on video to see if the screen turns on during these random wake-ups.
I don't know how to handle this problem, or at least, how to get Mazda to acknowledge the problem. This requires a really good engineer who understands exactly how everything works — like an automotive version of Dr. House.
I understand you have tried different dealerships, but it could be all of the ones you have been to are inept and unwilling to dig. You may have to go to another one if it's reasonable. The thing is, you are still under the bumper to bumper 36k warranty and should be able to have this fixed. It could even be lemon law territory depending on your state as they can't seems to get a handle on it and it keeps recurring.
I understand you have tried different dealerships, but it could be all of the ones you have been to are inept and unwilling to dig. You may have to go to another one if it's reasonable. The thing is, you are still under the bumper to bumper 36k warranty and should be able to have this fixed. It could even be lemon law territory depending on your state as they can't seems to get a handle on it and it keeps recurring.
The Lemon law first statement is an on going issues that can’t be resolved.
As the op indicated it has not happened when it was at the service department so it does not qualify for a states Lemon law. Yet!
Until he is willing to
Leave it at the dealership the problem is not going to be found, is not going to be a warranty and not found to be a manufactured problem…..yet!
we can post all the you should you want ….but until the advise given what he should do nothing is going to get found to solve?
Hello. CX5, 02/2024, 15000 miles. 1. About a month ago, we found the vehicle completely dead because the battery was drained. It had been sitting unused for 4 days. 2. We recharged the battery, and everything worked fine for a few days—until the same thing happened again after the car sat for 3 days. 3. I used a voltage logger (with its own battery, recording voltage every minute) to monitor the battery. Normally, the car goes into sleep mode about 5 minutes after it's turned off, using very little power. It can stay like that for 1,2 or more days, but then, without anyone touching it, it suddenly goes to erratic behavior with periods of wakes ups and sleeps. The power draw increases, which we can see from small drops in battery voltage (see Figure 1). 4. Once, we got a “keyless system malfunction” warning and the start button was blinking, even though both of our key fobs were working normally. Disconnecting and reconnecting the battery fixed it.
Obviously, there is some electronic module inside that erratically push vehicle in some wake up-sleep cycles which drain battery fast.
At a dealership I was told they cannot investigate or fix the problem unless it's actively present at the time of visit. They replaced the battery, but of course it did not help.
Any advice what I can do? Now I'm just disconnect the battery if the vehicle stay more than a couple of days. This is very annoying.
May be I can report to Mazda headquarter department somehow? Probably they have some repair statistics of similar problem? After 10 hours of normal stay (sleep) some electronics inside goes into wake-up sleep cycles. It drains battery fast. After about 3 hours of driving the vehicle was OK for 2 days. But any moment it can happen again
I try to go simple on this stuff - hopefully a 2024 --it is ! There was in issue with the CX30s in which they had a near identical issue - and it started occurring on more and more vehicles ---= Mazda dealer found the issue ....The proximity for the key fob is 15 meters and all the battery drains and hatch openings were attributed to the Key FOB being stored near the vehicle and or with a person who left it in their purse/ coat etc within that perimeter- I dont think its been an issue on the CX5 yet ---it sounds similar --as if the vehicle is not going to sleep - or waking back up from the FOB itself --hope it helps
Its basic 101 How to use and measure electrical current used.
Maybe take some time and do some reading like the first thing ... How to understand the Automotive 12 volt electrical system
Then invest in the simple electrical testing equipment.
new member here chasing the same problem. Callisto, you should be ashamed of your response. The CX-5 has an issue with killing batteries, and the dealers know it.
My current theory is the wi-fi remote interface.
The average modern vehicle battery life is only 3-5 years.
Like most new vehicles, the CX-5 OEM not very good.
I replaced my 2020 OEM the first year with a high-end battery and have had zero issues since.
My CX-5 is only used once a week on average.
I keep my FOB(s) over 25' from the vehicles.
I also have my wife's cellphone set-up to connect with our home wi-fi when she is in range, and not the CX-5 or her Buick Encore.
Pulling the fuses only isolates what is on that circuit. It could be one or multiple items and it tells you nothing about any actual wiring/crossed wiring issues that might be present on that circuit or being affected by another circuit fuse/breaker.
And with an average of 75 of them in the CX-5 it is very time consuming.
Especially when some are for "protection of various systems" which will require schematics and who knows what else to identify (all labor-intensive time).
A crusty electrical engineer is not the same as an up-to-date service trained Mazda technician.
I get my vehicles serviced at a dealership and a local garage with up-to-date trained service technicians.
Businesses are just like people good, bad and indifferent and it up to us to choose wisely.
After all when we complain about vehcile service anywhere, we are the ones who chose to go there, so we are actually complaining about our own decision making.
Have you done much electrical troubleshooting in the past? When you have little to nothing to go on, you start with the basics and pulling fuses, even if there are multiple devices on the circuit, will help identify which device is the problem. Even if there are 10 devices on that circuit at least now you know that it's one of those 10 and you can proceed accordingly.
It seems that you have the dealerships do your work for you so why are you advising on this subject?
