[cgtheboy]

Has anyone got the door locks to work after performing this battery replacement. I ask because my door locks and trunk still don't after replacing the battery. Car starts but no locks.

[cgtheboy]

get one of these

:https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1


and one of these :

https://www.ebay.com/itm/2pcs-5V-1A-...57872.m2749.Nw

Grab and old 5volt micro usb cell phone charger and cable Bust open your keyfob . Solder the wires to the charging board as shown .Tack with solder or alligator clip to the positive and negative of your battery, positive is the top of the battery . BTW You dont need to unsolder your battery from the board if it still holds a charge of course. Check your battery voltage in about 30 minutes . If its over 4 volts your done. Voltage will settle around 3.2 or so. Your non C/A keyfob battery is a little bigger so cut those little tabs out of the new case to make it fit. Stanley knife works fine for this. Snap it back together . Use your new key more often.

[general8297]

I have had two keys for the last couple years, one of them died and the other one was getting low. I did a lot of research and found out that a toothbrush charger would recharge the battery. I left the dead key fob on the charger overnight- when I went to try it it did not unlock the car but after driving to work the first day it works like a charm. I still don't get very much range, probably due to the tint on the car but it works. Free fix if you have a motorized toothbrush. I was going to take the fob apart and get a battery and change it but boy am I happy that I found out it was rechargeable.

[austin.tillison]

Originally Posted by cgtheboy

Has anyone got the door locks to work after performing this battery replacement. I ask because my door locks and trunk still don't after replacing the battery. Car starts but no locks.

I replaced my fob battery and still no luck.
None of the remote functions work.
I've been trying to get it sorted out for months and I'm stumped.

[Katsuo119]

Originally Posted by IllestBeams94

Hello fellow e9x's,

I have a problem and i don't know what to do..

My non comfort Access key fob has died a couple months ago, now i know they're suppose to charge while i drive, and i haven't even tried to use it for a couple of months now, but im starting to miss the fact that i cannot open my doors anymore at the simple click of a button. sometimes it use to work, then it didn't, now it doesnt work at all. i did have a second key, but it got lost somehow during hurricane Sandy. anyway, back to the real question(s)

- is there a way to open up the keyfob and change the battery?
- is there a way to buy a used keyfob and reprogram?
- could it possibly be the car thats malfunctioning?

thanks alot !

I'm looking for the reprogramming part myself but as far as opening it up, it's pretty easy. The things you'll need to do this is a knife, a steak knife works pretty good just be careful, a vl2020 90 degree battery, and some super glue, I used some liquid super glue which worked pretty good. Around the key there's a gap, all you have to do is run a knife along that gap and push down with a little force and that should pry it open just try not to push too hard. Once you have it open you'll need a soldering iron to remove the battery from the internal component. After the battery is removed all you do is resolder the battery to the main component and seal it up with some super glue. Hope this helps some!

-V

[BenjiFACE]

I just did the same replacement. My lock/unlock buttons do not work. I will try driving it around, I was disappointing when the replacement battery only had a voltage of 2.7V hopefully it just needs charging.

[MEN54]

Originally Posted by BenjiFACE

I just did the same replacement. My lock/unlock buttons do not work. I will try driving it around, I was disappointing when the replacement battery only had a voltage of 2.7V hopefully it just needs charging.

any update on this?

[quebix]

i also did the battery replacement.

lock / unlock doesnt work, but the key starts the car.

any solution?

[Hoff]

Originally Posted by pillbox

I have the same problem! Here's what I've done so far:

Check if it is the fuse(s) that have blown, causing the doors to unable to be unlocked. Your fuse board is on the firewall, behind your passenger side cubby. There are two 90 degree turn screws that you just turn left to open. There is an orange tool clipped onto the fuse board that you can use to remove the fuses. Be really careful and try not to drop fuses and the tool down inside!

Open your key fob by taking out the manual key, and splitting open the fob with a small flat-head screwdriver, or a utility blade.
ONCE YOU OPEN THE FOB, YOU WILL NEED TO RE-SEAL IT WITH SUPER-GLUE OR EQUIVALENT ADHESIVE (AFTER SANDING DOWN OLD ADHESIVE). KEY FOB WILL STILL WORK WHILE IT IS UN-SEALED AS LONG AS A RUBBER BAND IS HOLDING IT TOGETHER.


These are the solder points that hold down the battery.


This is the battery (Panasonic VL2020)


Order the battery by searching around on google, it will come with the BMW-specific contact points. I recommend using a small soldering pen to remove the old solders and to solder on the new battery.

I'm still waiting for my battery and new housing (current one is beat up) to arrive. Good luck!

Absolutely correct

If your battery is low, should be around 3v

Mine was 1.5v before changing

Replace if you are smart enough

No recoding required

Just follow this process and all good

If it doesn’t work it’s another problem

Cheers
Rick

[sub150]

Originally Posted by general8297

I have had two keys for the last couple years, one of them died and the other one was getting low. I did a lot of research and found out that a toothbrush charger would recharge the battery. I left the dead key fob on the charger overnight- when I went to try it it did not unlock the car but after driving to work the first day it works like a charm. I still don't get very much range, probably due to the tint on the car but it works. Free fix if you have a motorized toothbrush. I was going to take the fob apart and get a battery and change it but boy am I happy that I found out it was rechargeable.

Has anyone tried this?

I have two keys and both are low battery.

[e91Owner]

Originally Posted by sub150

Has anyone tried this?

I have two keys and both are low battery.

Yes, it works, but if you use your key regularly and are having to resort to this, you need a new battery.

[sub150]

Originally Posted by e91Owner

Yes, it works, but if you use your key regularly and are having to resort to this, you need a new battery.

Thanks. I have two keys. One I have used a little bit more now including a couple longer drives and it no longer says low battery. The other one is just a spare and I'm just going to let it sit dead/nearly dead? Both keys didn't get used for a few months.

I'll probably add it to the project list to replace both batteries, or just do the CA retromod

[ctuna]

You can put those on a wireless charger for a tooth brush or cell phone
and it will charge them . Any inductive charger should work.

On guy made and offline charger out of the socket you insert the key into.

https://www.bimmerfest.com/forums/sh...d.php?t=874226

https://www.e90post.com/forums/showt...ht=key+charger

[cgrizzly888]

Anyone have a good recommendation on a quality replacement 2020 battery for a non CAS key fob? Thanks

[LePucco]

Originally Posted by cgtheboy

get one of these

:https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1


and one of these :

https://www.ebay.com/itm/2pcs-5V-1A-...57872.m2749.Nw

Grab and old 5volt micro usb cell phone charger and cable Bust open your keyfob . Solder the wires to the charging board as shown .Tack with solder or alligator clip to the positive and negative of your battery, positive is the top of the battery . BTW You dont need to unsolder your battery from the board if it still holds a charge of course. Check your battery voltage in about 30 minutes . If its over 4 volts your done. Voltage will settle around 3.2 or so. Your non C/A keyfob battery is a little bigger so cut those little tabs out of the new case to make it fit. Stanley knife works fine for this. Snap it back together . Use your new key more often.

I know this is fairly old but could you please advise what is the ebay thing you got? the link is dead. I am having the same issue. I replaced the battery on one and its not working... but I belive this could be a solution for me.