I figured out how to repair my dead key fob on my 2006 Cooper S (R53). Obviously, it was the battery. The dealer offered no help, other than to sell me a new fob ($150! No extra charge for programming).

Through the internet, I found reference to the battery, a Panasonic 2020. I think I paid $6 plus shipping. This was marketed for various BMW models. What I didn't know was that the soldering terminals on a 2020 can be in different locations.

The fob is sonically welded, and not intended to be opened. I cut open my fob using a rotary tool and small cut off wheel. This cut out way more material than was necessary. (Doing it again, I would use a sharp utility knife, and cut carefully around the perimeter. Wearing heavy gloves).

Opening it up, I found that the battery was indeed a Panasonic 2020, but the soldering terminals were located closer together (about 75 degrees apart) than on my replacement (terminals at 180 degrees). This was remedied with a little piece of jumper wire and some gentle bending of the terminals. I should mention that a little de-soldering wick would have been handy in removing the old battery from the circuit board.

Immediately upon making the battery connection, I tested the circuit board by pressing the microswitches, and it worked perfectly.

I welded the case back together using a soldering gun with a flat tip. I then reshaped it using a file and a rasp. It now looks a little battered, but it's perfectly functional.

For $8, instead of 150, I again have a fully functional key fob, and will go several more years of clicking to open door and hatch, instead of reaching for the door, then having to walk back to the hatch.

I know BMW doesn't make these fobs, but maybe through protests of customer dis-satisfaction, and enough of them, the message could get back to BMW to make a fob with a user-replaceable battery.

 

Great work!!
This should IMO be a sticky once it is verified!!
Great work again!!

 

It's cosmetically a little rough. There was a little white polyethylene left over on the Weller soldering gun I used, so that got melted in. My goal was to make this key fob usable again, and it seems to be perfectly so. I so much enjoy walking up to the car and clicking instead of looking for the keyhole, especially in the dark.

 

It's been a week, and the key fob is still working perfectly. Since my last post, I found the Panasonic web site that lists the specifications for the VL2020 battery. The battery is rated for 1,000 recharges. That would seem to be several years worth, consistent with my own experience.

The VL2020 is available from Panasonic with a wide variety of terminal configurations. As of this writing, I don't know how to find the VL2020 with the exact configuration of the Mini key fob. I made the one I got to work with a little jumper wire, but I would have preferred to have soldered both connections to the circuit board.

I'd like to know of other's experiences.

 

I do repairs of 2001-2004 keys. i have been asked to try repairing 2005-2006 keys and declined because the battery is soldered in place and they are sonically welded together.

I did some research and found these sites:

http://www.bmwgm5.com/default.htm

http://bmwkey.com/

I did confirm with the first one that they will work on your MINI three button key, since it's essentially the same thing as a BMW key.

Kudos to you on your DIY repair but not everybody has access to or should use a soldering iron. If you're in that second group you may want to contact one of the above repair facilities (neither of which I'm affiliated with).

Val

 

I used a smaller soldering pencil to unsolder the old battery and to solder the new one in place (with a short piece of jumper wire).

A Weller soldering gun is available new for $34.95, less than either of the two services recommended ($50 and $59, plus postage), or even used for $20 or less. This one is identical to what I used (with the flat tip in the original Weller kit):

http://www.ebay.com/itm/VINTAGE-WELLER-8200N-SOLDERING-GUN-IRON-w-LIGHT-100-140-Watts-working-/400581425689?pt=LH_DefaultDomain_0&hash=item5d44837a19
The key fob is a soft polyethylene plastic, and the welding part was not especially difficult. I just held the two key halves together and melted and smeared the edges together.

I paid $4.50 for the battery, and $4.49 shipping ($8.99 total) from R-Isales on Amazon.

I appreciate the links. I looked at the first seller's "Wall of Shame" of attempted DIY repairs, and it's pretty enlightening. It also helps visualize what is inside the key, if you haven't seen it. I see that others had the same idea I had to use a piece of jumper wire to adapt the battery terminals.

With regard to the various types of damage shown on the Wall of Shame, I would surmise that most were caused by careless soldering, getting the circuit board too hot, or by careless opening of the key case. My suggestion would be to use the smallest soldering pencil you have to do the desoldering and soldering, and be careful not to heat the circuit board, not to apply heat directly to the battery case and only to the terminal ends, and doing so briefly. The terminals are laser welded to the battery case, and removing them will damage the battery.

When I attempted my DIY, I didn't care that much if it didn't work, since my investment to that point was only $9, and, if it didn't work, I was no worse off than I started. I still had my backup key fob. Knowing what I know now, I would definitely do it again before spending $150 or even $50 for a service that would likely take a couple of weeks at a minimum.

 

Also, it should be noted that lithium batteries can explode if too much heat is applied. Here is the Material Safety Datasheet for this type of Panasonic Battery:

http://www.panasonic.com/industrial/...mVL_F_Info.pdf

This is why the leads are welded on- the process is so quick that the internal temperature is not allowed to rise past the 100 C/212 F mark. Careless soldering, even on a battery that has welded leads, could raise the internal temperature past this mark. I've never actually seen a lithium battery explode, although I'm sure a search on YouTube would reveal examples of this.

Your point about making these keys with a battery that can't be easily changed out is valid. My guess is that it was to standardize the key type across the BMW family as this is almost identical to a BMW three button key. The 01-04 MINIs had a different type of key- a two button type that was clamshell shaped. This type used a button type lithium cell as well but it is not rechargeable and is user replaceable. I can see no reason to switch to the three button rechargeable type when they did the '05 refresh, except to standardize the keys and to plan the obsolescence of them so that the dealers can sell new ones.

Val

 

Hmmm...interesting. would something like this work with a 3 button key:

http://www.ebay.com/itm/New-Complete...W/121347627777

 

I can't tell at that price if it is a transplant-your-bits-into-it-shell or a complete key. I'm not that familiar with the three button keys, but if you can find a way to do the programming it might work. Not too much money to experiment with if you can find a way to program it. I would try that first and if you can get it to work, only then get the blade cut. In my area the blade cutting it about $35.

Bruce

 

that ebay link is for a complete flip key with remote.

My wife lost one of the 06 3 button remote keys. I was quoted 150 to get the replacement from the dealer. I'm thinking about getting the 50 dollar key and a used three button key fob like another guy did. I would LOVE a flip key but the MINI flip key empty cases on ebay are only for two button remotes.

How similar is the 3 button MINI key to the 3 button BMW "diamond" key? was your earlier statement just a figure of speech or are the guts exactly the same?

I'm about to start calling around to locksmiths in my area. I have to think where I live there might be one who can cut a key and maybe even register the EWS. It sure would be easy if I can get the key from my ebay link and have a locksmith set it up.

 

I've not had either of the three button keys in my hand, but my observations of what turned up on an image search for both circuit boards reveals that they appear to be almost identical, right down to the component placement and circuit board etching. Are they so similar that a BMW key will work with a MINI? That I can't tell from looking at circuit board images.

Bruce

 

I'd love to give it a shot, but I actually found the key last night my wife was looking for for a week. It was in her purse...where everything gets lost.

But I did order an empty case for a 2 button mini flip fob since it was less than ten bucks. I want to take a close look at the inside and see if it's possible to get two of the three buttons to line up in there.

 

Let us know how the flip case looks. Would love one of those.

 

It's been a year, now, and this fob repair is still holding up. Key still works like new.

 

For the record, I tried this on my 07 R52 - so if I understand the designations right, it's like the 05-06 keys (the cabrio being a hybrid generation car). I had tried to recharge it for a few days but it would not open the car remotely - it was good to drive though.

Well like an idiot, once I had the key open and found the sonically welded battery, the first thing I did was detach the welds. Not fun and risky to your fingers... As it turned out, the battery was NOT the problem. It was a tad low but not zero. 2.9V I think. Don't be me, check the voltage before proceeding !! I was so convinced it was dead (same issue in my wife's land rover) !

I soldered the new battery on and verified I had not destroyed it with quick solders (nope, still good, 3.x V, can't remember). Closed the key, with superglue - it looks perfect - but still does not work for *****. Doesn't help that the soldering point are slightly thicker and make pressing the close button harder (I suspect that is why the programming trick did not work for me - afraid to lose my good one doing that too), but really the key won't work, even when charged. I guess $150 for a fresh one is not so bad.

Side note: I reused the "supposedly dead" battery in my wife's spare land rover key - more room there. Doesn't work either. 0 for 2 ! Gonna put away the soldering iron and start signing checks instead ;-( Or see if I can somehow do a thinner solder job or sink the board deeper into the key and retry the programming trick... Then the key will look really bad ;-)

 

As a follow up, this key has since died. So I got about a little more than a year with my repair.

Now, I don't know if it was worth the bother.

But I can't bring myself to grovel to the dealer for a $150 new key.

I'm just opening the car the old-fashioned way, sticking the key into the door slot!

 

So is there any way to determine, for certain, that the key fob is the problem and not the receiver? I'd hate to buy a new one (or have this one fixed) and then have it not work.

Don't know any other mini owners so borrowing a key to reprogram temporarily is out. I tried the reprogramming procedure found here with no luck on my current key. I just bought the vehicle (for my daughter) and I'm assuming the battery is probably dead since it's an '06. It's the one and only key that I have. Will probably buy a spare soon but I'm trying to determine remote or not. I thought of buying a cheap remote key on ebay but I'm not sure I'd trust a key that may or may not work to begin with; anyone done this?

I'm a "give it a try myself" guy usually, already bought a battery (VL2020 w/ 90 degree terminals) but I'm hesitant to screw up my one key, and the internet "pro" I've found so far charges $50 so that seems reasonable. My local dealership parts guy said about $160 for the remote key and that it's easy to self-program.

 

I had no problem determining that it was the fob. My other fob which I kept in reserve (car came with two) still works perfectly.

By the way, this repair only worked for about a year then gave up. I haven't bothered to try to repair it again. I'm just annoyed with the whole thing.

My VW van came with a fob that uses a replaceable battery. I transplanted the guts and RFID "Pill" into a new housing from ebay and it continues to work perfectly even after going through the wash in my jeans.

I doubt that you could get a functioning programmable key from ebay.

 

I might be the "pro" that you speak of- I've started to work on both the flat and also the hockey puck keys as well as the two button keys. I'd be happy to work on your key and would even use the battery you bought- I'm not picky. My recommendation is to try the re-pairing procedures on this page: https://sites.google.com/site/minian...moving-forward

(make sure you go to the '05-'06 section) and if that doesn't work you can get a "general, non-remote" key at the dealer that will work with your car but doesn't have remote functions; it's around $100. Once you have that I can look at your key and determine if the battery is dead and if it is actually transmitting a signal. This will help you determine if the key is the problem or if it's the receiver. You can contact me at "minikeyhospital (at) outlook {doot} com.

Thanks-

Dr. Bruce Hart
MINI Key Hospital

 

Thanks Dr.

I saw your posts but didn't think you messed with the 05-06 rechargeable 3-button keys. I'll check out the link and see about a spare and maybe look you back up in a bit.

 

Great info in the link, thanks. That's the pairing procedure I tried (a few times).

Is the "R" position the first acc stop or the 2nd "on" position? Pretty sure I tried both, but will try again to be certain.

That's what I had thought on the eBay keys, maybe get one and remove the metal and just use it as a remote fob with a non-remote (or my non-functional) key.

 

Nice repair, but if it's your ONLY key you could end up stranded someplace only having to call Road Side Assistance or AAA....and they're not cheap either.

Up to 05 they had replaceable batteries, and for 2nd gen all models with comfort access have them as well.

$150.00 isnt bad. Last week customer told me they paid $600.00 for Nissan replacement key...One for my Honda Element with programming is $180.00.

Good luck with that.

 

Yeah, I hate new cars. $600 for a key?! What was so bad about a rectangular key for the ignition and an oval key that you have to stick in the locks for the doors and trunk?

 

I replaced a battery in one of my R53 clamshell keyfobs using a non-90 degree Panasonic VL2020. I used a small wire to jump the positive terminal, which I also trimmed, to the circuit board. I soldered the negative terminal directly into the board and then glued the pieces back together. Been working great for a couple weeks now.

I ordered a VL2020 that allegedly have the 90 degree pins, I'm waiting for it to show up to replace in my other key.

 

I ordered this battery and replaced the one on my second key fob. If you are careful cutting it open and use a few dabs of superglue to put it back together, it's an easy job and looks pretty good. This battery had the correct 90 degree tabs so it was a breeze, took me less than 10 minutes. I've done both the jumper wire on a 180 degree VL2020 and a 90 degree VL2020. They are both easy to do, but the correct battery is definitely easier.

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