2017~2021 Trunk opening randomly

:
2018 Mazda CX5 Machine Gray
Throwing this out there to see if this is an isolated issue or other people have had this issue.

Has anyone else come back to their trunk/rear hatch open when you know for a fact that it was closed and locked when you walked away. This has happened 3 times in the 2 yrs I've owned my 18' cx5.

The first time I lost my computer and every single picture on an external hard drive.


2nd time nothing was missing and this 3rd time was in my driveway overnight with nothing missing but I hadn't used the trunk at all. I have no idea what's going on and it happens so infrequently that I can't replicate it at the dealership. My guess is that I sometimes keep my key in my back pocket and if I'm within range if there is a small coin or gadget in my pocket the truck button is pressed? I've moved my key to the front pocket but now I'm super paranoid if I have to leave anything valuable in the car for any length of time.

A better design would require two key presses over a long key hold... Or a recessed button.
 
:
2019 CX-5 Signature
.. My guess is that I sometimes keep my key in my back pocket and if I'm within range if there is a small coin or gadget in my pocket the truck button is pressed? ...
Bingo! Honda's have a worse issue, where it opens their sunroof and windows. No way to disable that "feature", either.

Putting the fob in your front pocket should help. As long as you don't have other items in it that could accidentally trigger it. Maybe check out some fob covers that would make it more difficult.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
Throwing this out there to see if this is an isolated issue or other people have had this issue.

Has anyone else come back to their trunk/rear hatch open when you know for a fact that it was closed and locked when you walked away. This has happened 3 times in the 2 yrs I've owned my 18' cx5.

The first time I lost my computer and every single picture on an external hard drive.


2nd time nothing was missing and this 3rd time was in my driveway overnight with nothing missing but I hadn't used the trunk at all. I have no idea what's going on and it happens so infrequently that I can't replicate it at the dealership. My guess is that I sometimes keep my key in my back pocket and if I'm within range if there is a small coin or gadget in my pocket the truck button is pressed? I've moved my key to the front pocket but now I'm super paranoid if I have to leave anything valuable in the car for any length of time.

A better design would require two key presses over a long key hold... Or a recessed button.
Actually we’ve seen the same complaint on power liftgate here before on gen-2 CX-5 such as these:

Rear hatch opening by itself????

disable liftgate remote on fob . 2018 cx-5

No cause and resolution could be reached.
 
(Didn't realize this was in a CX-5 thread until after I created an account and Replied. My Bad.)

Yes! I have been complaining about this on our 2018 CX-9 GT since June when it opened while my wife was backing out of the garage and broke some rear trim pieces. It had and has happened maybe 6 times in the 2 years we've owned the vehicle. Had it in the dealership for a couple weeks in the end of June and of course they couldn't find anything and told me to deal with corporate.... I think it has to do with the recall due to faulty wiring harnesses that came out right around that time. Bringing it back to have the recall fixed and am going to fight to have the trim fixed as well. Here is some info on the recall:

https://mazda.oemdtc.com/1360/2018-mazda-cx-9-front-and-rear-harness-concern-recall-3419e

Can anyone tell me if the C-47 and C-48 harnesses or any of the 8 harnesses they are replacing as part of the recall have control of the rear liftgate?

Thanks!

More info on recall from NHTSA:
 
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:
Toronto, ON Canada
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2017 CX-5 GT
The 2020 models get the new larger square fob that debuted with the 2019 Mazda 3. The buttons are on the side so we'll have to see if this is any better than the fobs for the 2017-2019.
 
Seen this complaint before but not sure it ever had a resolution.
On my '09 Corvette, I had great success with a silicone rubber protective fob cover. Like this one from TheJacketStore:
fob cover TheJacketStore.gif

Custom fit, secure grip, nice cushion. And a bright color is less likely to be misplaced.

Full coverage might be more effective:
fob covers 1a.jpg

And a different color for different fobs. But I've never tried full coverage, so can't say if it works better.

Maybe a leather case?
fob leather pouch.jpg

But obviously you have to open the case to press a button. Too inconvenient for me.

I'm guessing the buttons are less sensitive with a leather cover like this:
fob leather pouch 1a.jpg


Bottom Line:
4 reasons to try a protective cover: https://www.thejacketstore.com/store/pc/key-fob-product-features.asp
 
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Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
I've not had that issue, but purchased one of these fobs on recommendation of a fellow member:



This is an enclosed case. The fob goes in the back and then the rear cover slides into place. You have to push the icons on the case (they are screened onto a solid film) in order to engage the buttons on the encased fob. I don't use the fob to control the doors or locks, so it always stays in my pocket...this keeps the dust out, and provides the added benefit of requiring more pressure to engage any of the fob's buttons so it does not happen accidentally.
 

7eregrine

The man, the myth, the legend
:
Land of Cleve
:
2016.5 CX5
That is the nicest fob thing I've ever seen. Is it that nice in person? Never considered buying one before...until now. :D

No one is going to convince me that this "issue" isn't user error.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
That is the nicest fob thing I've ever seen. Is it that nice in person? Never considered buying one before...until now. :D

No one is going to convince me that this "issue" isn't user error.
The issue with the blue one (and likely the red) is that the color is so dark, there's little contrast with the screened-on black icons in some conditions. It's not like the picture. Indoors, under incandescent lighting, you have to be at just the right angle to see each icon; otherwise, the entire thing is one dark mass.

When I first got it, I made sure to look at it in a marginally lit parking lot at night to see if this was going to be a significant issue, and the contrast was sufficient...under those specific conditions. I suspect the lighter colors give better contrast. And the only lighting conditions where I've had the "completely fades out at the right angle" issue has been directly under incandescent lighting.

Keep in mind the thing never leaves my pocket, so I never use it. I have "Walk Away" door locking turned on, always use the button on the door handle to unlock it, and always open the rear hatch by the dash or at-hatch buttons.

That being said, I like it. The fob is completely enclosed in the case to keep dust & lint off of the buttons. The case has a nice "heft" to it. It matches my car. I have one for each fob, even though I'm the only driver, so as to keep the spare dust-free.

I forget which member here recommended this. Maybe he can chime in on his color and icon-contrast.
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
This hasn't happened to me (yet), but as a precaution I've minimized what's on my keyring (only keyfob, house keys, mailbox key and LED flashlight). I also purposefully "separate" the keyfob from the other keys when I put my keys in my pocket. I never take my keys out until I need them, and they stay like this throughout the day. No accidental unlocks or trunk openings to date.

IMG_20200107_091612.jpg
IMG_20200107_091643.jpg
 

rockethead26

2019 CX-5 Reserve
:
N. Arizona @ 7000'
I forget which member here recommended this. Maybe he can chime in on his color and icon-contrast.
That was me, I'm pretty sure. My wife and I use the red one, but I haven't been in a lighting condition where I have been unable to see which button was which. That said, I'm like Avoidin in that I rarely take it out of my pocket. It's only been 7 weeks since I started using the cover, but it still looks brand new and I've put 1200 miles on the car. This is a very nice, not too big fob cover.

No accidental trunk openings to date for either me or my wife.
 

7eregrine

The man, the myth, the legend
:
Land of Cleve
:
2016.5 CX5
That being said, I like it. The fob is completely enclosed in the case to keep dust & lint off of the buttons. The case has a nice "heft" to it. It matches my car. I have one for each fob, even though I'm the only driver, so as to keep the spare dust-free.
Have a real problem with dust, do ya'? :D

LMAO at Smike showing us a picture of his pocket.

I'll tell ya' one of the single best purchases I've ever made:
https://www.amazon.com/dp/B00NT1OX5K/?tag=m20b7-20
//edit// OK That sucks with new site. It doesn't shorten links? //edit//


= NO HOUSE KEY.
I only need my car key on me (with my remote start fob).

To answer the question, (because someone invariably always asks) it gives WEEKS worth of warning before the battery dies on it. Not to mention I have 2 of them, one on the front door and one on the garage door. The odds of both batteries failing at exactly the same time and locking me out are infinitesimal. Not to mention on new house I have access through attached garage. But I did use 2 of these on old house with no attached garage for years and never got locked out.
I thought about getting "Smart ones" but I just do not see the need yet to have a Google door lock so I can use my phone to unlock. A pin code lock is every bit as easy. So I can't unlock by voice... really, that's ok. :D I'm all in on SMART HOME but door locks. Meh.
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
LMAO at Smike showing us a picture of his pocket.
LOL I know. I will not deny that it is crazy of me to take a picture of my pocket and put a freaking outline on it in Paint, but honestly it's worked very well for me. I used to have a 99 Accord and I'd accidentally trip the Panic button on the key fob until I started doing this.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
Have a real problem with dust, do ya'? :D

LMAO at Smike showing us a picture of his pocket.

I'll tell ya' one of the single best purchases I've ever made:
First, I have no problem with dust at all. I've got plenty of it! Want some???

Re: Smike's pocket...It looks like a crime scene. "Looks like he used a boomerang, Sarge."

Regarding that lock: I've seen those before and never thought of putting one on my garage. Even though I'm in a very remote area, I hate leaving my garage unlocked. But I do because I don't carry my keys when I'm doing work around the homestead, and got tired of having to go back inside the house just so I could get into my garage. That's a great solution!!!
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
That was me, I'm pretty sure. My wife and I use the red one, but I haven't been in a lighting condition where I have been unable to see which button was which. That said, I'm like Avoidin in that I rarely take it out of my pocket. It's only been 7 weeks since I started using the cover, but it still looks brand new and I've put 1200 miles on the car. This is a very nice, not too big fob cover.

No accidental trunk openings to date for either me or my wife.
I love my fob. Thanks for the recommendation! I'm glad the red has no contrast issues. After I wrote my comment yesterday, I was outside (a sunny day) in the shadow of my garage. Looking straight on the fob, my reflection obscured the icons. I had to turn the fob to the side to see them.

Here are a couple of pics taken under a window to show you what I mean.

Standing back so I don't cast a reflection:
IMG_20200109_094933197_MP.jpg


The reflection of my cell phone on the two bottom icons.
The fob is pointing at the window...I'm not blocking the light.
IMG_20200109_094950601.jpg


I can rock the fob slightly to one side in many lighting conditions, and the entire front will black out. As I said, I never use it for anything but the transmitter. And if I did use it regularly, I would instinctively reach for the right button without looking. But this is how the blue one is.
 
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shadonoz

SkyActiv Member
Contributor
:
State of Jefferson
:
2017 CX-5 GT AWD+
Many unlicensed wireless devices use the same frequencies as these key fobs. A stray signal or interference could be the explanation for some of these random activations.
 

Avoidin Deer

Zoom Zoom, baby
Contributor
:
Central Virginia
:
2019 CX-5 Reserve
I was gonna suggest perhaps a faraday pouch for the fob...
https://www.amazon.com/dp/B07GDD35GH/?tag=m20b7-20

not so much another device opening the vehicle; but another device causing the fob to open the vehicle.
How would that work?

I'm not doubting you, but I don't understand how an errant signal could cause the fob to transmit. The buttons are [obviously] mechanical switches.
 
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