[KwlAznKid]

I've been doing a bunch of research on how to charge a non-comfort access key fob because my range has gone down to about 3 feet now which is ridiculous. Based on what I've found on multiple forums it seems that the best way to charge these batteries is to use a electric toothbrush charger (I thought it was a joke at first), has anyone done this before? All the examples I see online are the older generation key, haven't seen one with the e9x style square keys. If anyone has done it before do you have any advice on how to place the key?

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i also heard that using a wireless cell phone charging pad could work... so i tried this, usually when charging the phone the pad lights up to indicate it's charging but with the key on there it doesn't light up

[e90yyc]

I’ve done this before. Indeed the keys charge with wireless charging (god forbid BMW would just put in a user-replaceable battery...), but I honestly couldn’t tell you if it was just a rain dance or not. If I ever pop one open I’ll be sure to do some testing with the multimeter.

It makes sense the wireless charging pad doesn’t work, so I’d stick with the toothbrush charger.

As for placement, my best guess would be photo #1. If indeed your dismal fob range is due to low battery, hopefully you’ll see improvement. If not, try positioning it different perhaps.

To add: I seem to remember my key being a bit warm after some time on the charger. Based strictly on this, I figured it *probably* works .

[KwlAznKid]

Originally Posted by e90yyc

I’ve done this before. Indeed the keys charge with wireless charging (god forbid BMW would have wanted to put in a user-replaceable battery...), but I honestly couldn’t tell you if it was just a rain dance or not. If I ever pop one open I’ll be sure to do some testing with the multimeter.

It makes sense the wireless charging pad doesn’t work, so I’d stick with the toothbrush charger.

As for placement, my best guess would be photo #1. If indeed your dismal fob range is due to low battery, hopefully you’ll see improvement. If not, try positioning it different perhaps.

thanks! I'll try position 1 for 24 hrs and see if i notice a difference

[dakine_surf]

It doesn't have to touch, and it does indeed charge, but you should also be charging while driving... I'd look into the battery going bad or interference and or remote antennas going bad if it doesn't get better with a full nights charge

[Gamb1t]

Is it not charging in the key slot due to short drives? Road trip!!!!
Alternative is to hook up a battery tender to the car and turn on the car to charge the key.

[KwlAznKid]

Originally Posted by dakine_surf

It doesn't have to touch, and it does indeed charge, but you should also be charging while driving... I'd look into the battery going bad or interference and or remote antennas going bad if it doesn't get better with a full nights charge

Originally Posted by Gamb1t

Is it not charging in the key slot due to short drives? Road trip!!!!
Alternative is to hook up a battery tender to the car and turn on the car to charge the key.

i don't think the battery is going bad, i just only drive the car maybe once a week or so and not for long distances so it's probably not getting enough charge time lol

[N52bigblock]

After 13 years the battery will be pretty sad and not holding a full charge hence the reduced range. I opened my key up and replaced the battery. You can buy them on ebay. It's a bit fiddly getting the key open but once it's done the extra range you get is great!

[Schmitz]

Originally Posted by neilj35

After 13 years the battery will be pretty sad and not holding a full charge hence the reduced range. I opened my key up and replaced the battery. You can buy them on ebay. It's a bit fiddly getting the key open but once it's done the extra range you get is great!

Can you post where you got the battery from?

[ryan stewart]

Originally Posted by e90yyc

(god forbid BMW would just put in a user-replaceable battery...),

Its gotta only be a "cool thing we can do" type of thing because I cant see the coin cell battery being an issue. I have the comfort access key that is constantly talking to the car and the battery lasts a long time, and when it goes low it just drops to non-comfort access for a long time (ive never actually had it die).

Id think anymoe if it was JUST old-school youd probably get he entire warranty period out of a CR2032 battery.

[N52bigblock]

Originally Posted by Schmitz

Can you post where you got the battery from?

Just go onto Ebay and search for VL2020 battery. Amazon have them as well. https://www.amazon.com/Panasonic-VL2.../dp/B00D4522AY

[KwlAznKid]

so i put the battery in the position in picture 1 last night around 9pm and it's almost 4pm today, did a quick test and range increased significantly... i can't believe it! lol

[p1zaul]

I changed my e46 m3 battery as it was quite old with a new rechargable, it's not the easiest thing in the world as it needed tabs to be soldered onto the battery. i think this is because it is meant to be permanent. 100 times better though once replaced. I would try it out of you think you can solder the tab. not sure our e90s even have the soldered tab.

also if you swap it out, yet leaving it on a qi charger overnight. and the battery had to obviously be in the key to charge.

[EP11]

Do you mind posting a link to the toothbrush charger you used? Would really like to try this before opening up my fob.

[p1zaul]

Originally Posted by EP11

Do you mind posting a link to the toothbrush charger you used? Would really like to try this before opening up my fob.

try a qi first it should in theory work

[EP11]

Originally Posted by p1zaul

try a qi first it should in theory work

I tried one already but it doesn't work, it flashes meaning that there is some type of interference therefore not allowing it to start charging.

[Polaris15]

Just buy a new battery and install. It takes all of 5 minutes. Watch a youtube video.

[Hoff]

I changed out to a new battery
Non comfort.
Soldering the new one in and worked fine for the day but the following morning it was flat as tack

Done it twice now with the same result

It’s doing my head in

Any ideas 💡

[Ha4cnn]

I have a dead key fob the same as yours. I will leave it close to my electric toothbrush for a number of hours and let you know if it works.

[Hoff]

Originally Posted by Ha4cnn

I have a dead key fob the same as yours. I will leave it close to my electric toothbrush for a number of hours and let you know if it works.

Look forward to your experiment bud, I have tried the phone charger with no luck

It’s weird, maybe it’s the fob itself but I would hate to buy another and get a no result

Cheers Rick

[liquidsmoke]

Originally Posted by e90yyc

I’ve done this before. Indeed the keys charge with wireless charging (god forbid BMW would just put in a user-replaceable battery...), but I honestly couldn’t tell you if it was just a rain dance or not. If I ever pop one open I’ll be sure to do some testing with the multimeter.

It makes sense the wireless charging pad doesn’t work, so I’d stick with the toothbrush charger.

As for placement, my best guess would be photo #1. If indeed your dismal fob range is due to low battery, hopefully you’ll see improvement. If not, try positioning it different perhaps.

To add: I seem to remember my key being a bit warm after some time on the charger. Based strictly on this, I figured it *probably* works .

I did get a wireless charger to try to resurrect my fob that’s not working for remote locking; but i don’t think it’s gonna work, cos it seems like the charger pad doesn’t stay online when I only have the key fob placed on it…ie when I put my phone on it, it stays online with led indicator to show its charging it up, but if there’s only the key on it, it doesn’t stay online…
This is the one I’m trying:
yootech Wireless Charger,10W Max Fast Wireless Phone Charging Pad Compatible with iPhone 14/14 Plus/14 Pro/14 Pro Max/13 Pro Max/13/13 Mini/SE 2022,Samsung Galaxy S22/S21,AirPods Pro(No AC Adapter) https://amzn.eu/d/9qY9hqx

Does anyone know if there’s a different charger that will stay online even if there’s only a key placed on it?

[BRG_N54]

You need to get an inductive charger that does not use Qi signaling. The charger you have does a handshake with the device (Qi) to enable the charging coils. You need one that is always on, like a toothbrush or desk accessory type. If you search for "wireless charger for non qi enabled devices" it turns up quite a few options, good luck!

[pedro2u]

Originally Posted by Gamb1t

Is it not charging in the key slot due to short drives? Road trip!!!!
Alternative is to hook up a battery tender to the car and turn on the car to charge the key.

I had 1 dead key when I bought my ZHP. I tried many things, but the fix was putting a charger on the car. then putting the key in the ignition with it turned on to the run position (but not running). Left it on overnight and my key was recharged by morning. E46 and E90 have the same inductive charging ring for the keys, so should work here too. Certainly worth a try!