2021 Key Battery Low

So today was interesting - I've had my 2021 GTR for four days, and today the car wouldn't start because the battery in the key was low. Held the key near the start button and that allowed the car to start. The battery was still strong enough to lock and unlock the car from a distance, which seems odd.

Thought I'd get this out there and see if anyone else had this happen. Hopefully just a bad battery. Will have to watch it.
 
:
2021 CX-5T AWD CE
Symptoms don’t seem consistent with it being a bad battery, although it’s certainly the first thing to try. Do you have the fob on a key ring? I have had some very weird starting issues on various cars with key rings and other gizmos on the ring.

- Mark
 
Thanks Mark. That's a good point. I have a leather strap on the fob, but also a Tile. I considered the BT in the Tile might interfere, but it worked flawlessly until last night. Didn't try the second fob.

I replaced the battery and the fob went back to working normally. If it happens again I'll try removing the Tile and see if that fixes the issue.
 
:
2020 CX5 Signature
My 2020 CX-5 Signature was purchased six weeks ago and today I had to hold the fob near the Start button for it to be recognized. Locking, Unlocking and opening the tailgate via the fob worked just fine from a distance, so it didn't seem like the battery, but I'm going to replace it and see what happens.
 
Sounds like what happened to me. The 2021 had a message on the dash that actually said "low battery", and told me to hold the fob near the start button.
 
:
2014 Mazda CX-5 GT AWD w/Tech
One thing we've heard of on here: if you keep your fob in the house but still somewhat near the vehicle in the garage, it may be constantly communicating with the vehicle because it's in range and wear down the battery. Just a thought.
 
:
Europe
:
2020 cx-5 GT
I have ordered today those Faraday pouches where I am going to keep the fob when not using the car, especially the spare one that stays most of the time close to the garage.
 
:
Pueblo county CO
:
CX-5 Sport 16.5 6M
I popped open my spare fob and wrapped the battery with a piece of plastic wrap. Hope the battery will be ok if the the other one dies, but the batteries were made the same date so there's no guarantee.
 
:
2018 CX-5 Sport
I popped open my spare fob and wrapped the battery with a piece of plastic wrap. Hope the battery will be ok if the the other one dies, but the batteries were made the same date so there's no guarantee.
If you have a multi-meter, check the voltage of the battery in the spare fob. I removed the battery not long after getting my car, and that battery was stone dead. It was never used. The battery supposed to have a 10 year shelf life according to the package of the new batteries.
 
:
Pueblo county CO
:
CX-5 Sport 16.5 6M
If you have a multi-meter, check the voltage of the battery in the spare fob. I removed the battery not long after getting my car, and that battery was stone dead. It was never used. The battery supposed to have a 10 year shelf life according to the package of the new batteries.
Right. I just replaced both of them when the one ran down. I hope the spare will have some juice if I need it, but I will probably replace both of them again in a couple of years.
 
:
2017 Mazda CX-5 GT, 2016 Mazda6 iGT, 2014 Mazda3 sGT hatchback
There is a way to shut down the spare fob completely. Search the forum. Very simple to deactivate and re-activate when needed.

My fobs typically last 2 yrs.
Keep you fob far away from your vehicles (some people leave their fobs in the garage. that is too close). Or, keep your fobs in a metal box. Tin foil works as well.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
It’s nice to get a new Q85 battery (very expensive) as you’re supposed to. Another member failed to get a new battery even though the voltage of his battery had dropped to 3.414V over night.
 
Last edited by a moderator:

Latest posts

Top