Problems with Parasitic Draws (2020 CX-5)

[Adam GS]

Hi. I have a parasitic draw of about 1.6A on a 2020 Mazda CX-5. Every couple of days or so the battery needs a jump. I pulled every fuse in the under-the-hood fuse box and found three contributors. F11 (~250ma “Electric Parking Brake – Right”), F28 (~200ma Transaxle Control System (some models), ignition switch”), and F54 (~500ma “Overhead Light”). The parking brake is “OFF” and the overhead lights are “OFF” so…. No easy fixes. No issues with the circuits fused in the box below/left of the steering wheel either. I’m also concerned that these three circuits only account for 60% of the parasitic draw! (250 + 200 + 500) / (1600) = 59%. Any ideas?

 

[rpanda]

I could not pull out the bigger size fuses (which include the 2 EPB fuses), so did not measure those circuits. My EPB is working properly.

Just to clarify, when I turn on EPB I hear the brake actuator working, so I assume it is working properly.

 

[rpanda]

Unfortunately (or not!) my model does not have a power rear hatch. Have an appointment at a dealership in two weeks - hoping it's a software update... but may continue to troubleshoot until then. Very appreciative of all the good feedback too!

Adam, please post the outcome when you get a diagnosis/fix from the dealer.

 

[edmaz]

I use it only when parking on high gradients (up-hill/down-hill).

I was hoping you replied that you used it all the time (which some people do), because that would have been a good possibility for this unexplained draw. If the EPB switch somehow becomes stuck closed, after the brake has been applied, then probably the 'close' logic would be retried continuously and would be a fit for multiple circuits remaining active. But it looks like that's not possible, given your EPB usage.

As I mentioned to the OP, if this were my problem, I'd continue to diagnose by pulling the remaining fuses in the engine bay and also the cabin fuse box. Identifying the complete set of fuses active during this parasitic draw IMO is an opportunity to gather additional information, which might be a key to diagnosing what's causing this draw.

However, if you're not up for putting more DIY into this problem, then I recommend going to an auto-electric shop instead of a dealership. Those guys should be able to eat a problem like this for lunch, without even breathing hard. And I don't believe the typical dealer service department would have a clue even where to begin on a situation like this, unless there happens to be a service alert from Mazda previously issued, which identifies the problem and provides a solution for it.

 

[yamahaha]

Not sure about the Mazda, but on a different (GM) car I was testing some years ago, as soon as you reconnected anything, the BCM would switch out of "battery save" mode and current would start flowing again. It may be that just reinserting the fuses is triggering that here too.

Absolutely. I foolishly chased a draw on a Ford this way and chased ghosts as I was reactivating things the entire time.

 

[rpanda]

My 2019 CX-5 has the same problem. It is drawing 1.8A parasitic. I measured and recorded the 'Room' circuit drawing ~800 mA and 'AT' circuit ~250 mA. Could not pull out the larger fuses to test the remaining circuits. Apparently (from other posts), the lift gate control may be one of the culprits, but I see the problem in multiple circuits. Planning to take to the dealer, but after reading other posts describing their experience with the dealers, I am not too hopeful they can fix it.

This is finally resolved. The culprit was the SnapShot device provided by Progressive Insurance that was plugged into the OBDII port. After unplugging it, the battery is holding charge/voltage. The current measurement of 1.8A that I observed was misleading. If you observe the current long enough (like 7 to 10 minutes), it comes down to less than 50 mA as circuits go to sleep.

 

[edmaz]

This is finally resolved. The culprit was the SnapShot device provided by Progressive Insurance that was plugged into the OBDII port. ....

It's unbelievable that they would do that, and frankly I never even thought about asking if anything was plugged in there. Did you contact Progressive to register a complaint about what they're doing to your vehicle (and presumably many others as well)?

 

[rpanda]

It's unbelievable that they would do that, and frankly I never even thought about asking if anything was plugged in there. Did you contact Progressive to register a complaint about what they're doing to your vehicle (and presumably many others as well)?

I plan to call Progressive and see what they have to say. Now googling about this problem, I see many have/had this problem.

 

[edmaz]

I plan to call Progressive and see what they have to say. Now googling about this problem, I see many have/had this problem.

It wouldn't be a surprise if you get one of those "we take your problem very seriously" replies, which actually means they could care less about what you have to say. But regardless of that, thanks for following up with what you found, and your resolution to the problem. Most people don't ever do that, and I'd expect that it might help others who read this thread in the future. Also, I edited my original reply to you, which was likely to be misleading to anyone else having the same problem as the OP.