i bought 12 varta battires...went through them within 1.5 years...yes, all 12 batteries. some only lasted 2 weeks. all these batteries are all hit or miss regardless of brand. maybe thats because my key was very far away from the car? also tried Maxell batteries...all the same. funny thing is the batteries at Daiso seem to be working the best for me.

 

Video showing how to replace the battery in the older style key fob.
2 batteries of CR2025 per key fob.
No reprogramming or reset needed after a battery replacement
Easy DIY !!

 

Did you ever fins a solution to this? I'm having the same issue with my Holden Spark. Despite them saying the customer care would continue for Holden owners, it no longer seems to be functioning. You can ring the 0800 number, but it just says to try back within work hours (which is when I'm ringing already).

 

My batteries have all been the 2032 ones, but no luck - the message just won't go away.

 

Get FRESH brand-name batteries from a reputable source... not from Amazon where they may have been sitting in an overseas shipping container for two years.

 

yep, only using reputable brand ones. The dealer suggested using the actual key to unlock and start the car, as he thought that would sync the remote. Made no sense to me as that key can be swapped between my 2 remotes anyway so isn't specific to each. Tried it anyway but it didn't work.

 

Dangit! I've been hit with this PITA myself tonight, but I think there's more to my issue.
Replaced the battery two months ago with a new 2025 based on the message. All was fine. Went and bought some beer tonight, a 7 mile round trip drive with no issues restarting at the store. Parked in the driveway at home, enjoyed a couple beers with me neighbor and then called it a night. Went to start the car to pull into the garage and saw the error. Only this time, the push to start didn't work either. Took the button out and inserted the key and received a message to remove the key. Got out, tested the fob by locking and unlocking the doors, and it's all good. Opened the door, was greeted with lights and the same replace battery error. So... replaced it. Tried both a 2025 and a 2032. Same events followed. No start, but all else seems to work fine. No prior symptoms of an impending ESL issue, so hoping it's the car battery. Threw the charger on for now and will disco the negative for a bit if the charging doesn't help. Will report back what I discover.
Update: ESL. On about the fifth try of putting the key in the ignition, I noticed a slight tick from it. Gave the wheel a couple thumps with my palm and it moved and then started. F me. Time for an emulator I guess. It'd be nice if the dash could tell you the wheel is locked instead of something completely unrelated. I also put the original battery back in and it's fine (for now).
Update 2: Installed an emulator after locating and removing the failing ESL. All is good now.

 

This.

After trying various of the suggested solutions on this thread I kept having the same "replace key battery" message. I tried 2 brand new batteries but no luck, one of them even made the key useless ("key not detected"). I then tested the batteries and sure enough, one of them was weak and the other completely drained out.

CR2032 works but I don't like this solution because the battery is hard to get in (and harder to get out), and it makes the key cover bloated, which also makes it prone to water infiltrations. With my former Mercedes one of my keys was accidentally left in a pocket in the washing machine, but after drying it was still working. Pretty sure it would be dead if it was bloated like this, since the cover doesn't properly fulfil its role anymore.

 

While a CR2032 is the same voltage as a CR2025, it is physically too thick to properly fit in the key. You might manage to jam one in, but you may also mangle up the key itself in the process.

 

My key worked after replacing the battery for the original CR2025, but after 2 months I got the same message again.
Following the advice which was posted here, I inserted the key and started the car instead of using the button to start the car.
I shut the car down and restarted using the button and the message was gone.

 

Had this issue too. Tried replacing battery in vehicle and hard resets with a multitude of diff. youtube suggestions but just changing to a CR2032 battery did the trick for me.
DollarTree brand lols but it works

2012 c63 here

 

E400. So my remote key came up with a low battery message. I replaced the battery with a new CR2025. .. message didn't go away ..I tried a number of solutions other people suggested and finally swapped to a new CR2032 battery. .. problem solved .. yet when I put either of the new batteries on the multi meter they show exactly the same voltage. .. it doesn't figure. The CR2032 is an impossibly tight fit for the dongle and getting it out is a real problem..for later. ..🫢 !!
Edit: the CR2032 battery actually fits and the spring contacts take up the additional thickness .. the plastic cover fits without any issues ..only removing the battery is a problem. ..but it can be pried out with a strong pin. ..🤙

 

This seems to have worked for me. Changed fob batteries 3x in the house. Finally got tired of the warning coming on telling me to change the batteries. So removed fob batteries whilst in the vehicle and car seems to reset thinking batteries were replaced.

 

Tried several new batteries - tried both keys (spearately and together) and message still won't go