This is a trivial problem in the grand scheme of things but it does bug me

Basically the spring in my fob doesn't have much 'spring' in it - when I press the fob button the key barely moves at all. Is there a way to replace the spring at all?

looks like your key could do with a new case which I believe comes with a new spring, only way to get to the spring is to pry the key open which you wont be able to put back together  RRS SUPERCHARGED, 22 INCH ALLOYS, JAVA BLACK, FULLY COLOUR CODED
EVERY POSSIBLE SOFTWARE UPDATE INCLUDING - BLUTOOTH UPDATE, SATNAV ON THE MOVE, CLOCK ON DASH, 3 CLICK FLASH, GEARBOX RESET, COMPRESSOR UPDATE AND SUSPENSION LOWERED,
BLACK CODE RE-MAPPED, AUTOBIOGRAPHY'D, NEW EXIDE BATTERY, NEW DENSO ALTERNATOR

Sounds like a plan - something like this?

http://www.ebay.co.uk/itm/Black-3-Button-R...418b58984f

Seems very cheap... Is it a fairly straightforward job to do?

yep thats the one, I think theres a video somewere on here or can check on youtube  RRS SUPERCHARGED, 22 INCH ALLOYS, JAVA BLACK, FULLY COLOUR CODED
EVERY POSSIBLE SOFTWARE UPDATE INCLUDING - BLUTOOTH UPDATE, SATNAV ON THE MOVE, CLOCK ON DASH, 3 CLICK FLASH, GEARBOX RESET, COMPRESSOR UPDATE AND SUSPENSION LOWERED,
BLACK CODE RE-MAPPED, AUTOBIOGRAPHY'D, NEW EXIDE BATTERY, NEW DENSO ALTERNATOR

As good as new now, for less than £6

Old one was a swine to open though, like you said, no chance of putting it back together afterwards. Think I will do my other fob now, looks much better in a fresh new case.

Click image to enlarge

Good job

Did you have to glue it shut again? I'm not Fat. RRS TDV6 HST.

I did mine, yes they have to be glued shut.  2010 RRS TDV6 3.0 Autobiography - Stornoway Grey
2006 RRS TDV6 2.7 HSE -Java Black
2008 BMW 3 Series 2.l
2006 BMW 5 series 2.l

Yeah, just used some epoxy resin around the inside edge and clamped it overnight.

Nice job but be warned epoxy doesn't stick to the case very well and it will come apart. Super glue however works perfectly.
 2008 MY Java Black TDV8 HSE

I tried polystyrene cement first but the plastic wasn't having any of that which is why I used the epoxy. Will see how it goes, if it all comes apart one day I'll give the superglue a try

Just out of interest the owners manual says the battery is rechargeable and recharges when the key is in the ignition... However now I've seen how they are made I don't see how that is possible as there is no connection between the key blade and the circuit board/battery? Anyone know how it works?

Know the feeling - I tried all sorts of adhesives without success until I found a Land Rover TSB about repairing key fob cases that specified cyanocrylate (i.e. super glue) and that was completely successful.

The battery recharges by the principle of induction so no physical connection is required.

The batteries don't last indefinitely (but can be changed now you know how to get the case apart) and not using the fob shortens the battery's life so it is a good idea to swop with your spare key every couple of weeks or so. 2008 MY Java Black TDV8 HSE

zaphod wrote:

Just out of interest the owners manual says the battery is rechargeable and recharges when the key is in the ignition... However now I've seen how they are made I don't see how that is possible as there is no connection between the key blade and the circuit board/battery? Anyone know how it works?

It charges via hall effect. http://en.wikipedia.org/wiki/Hall_effect  Visiting from DISCO3.CO.UK
2006 Discovery 3 TDV6 Auto HSE Zambezi Silver

Cheers guys, so basically it charges wirelessly like my phone. I'll try to make sure I use both fobs to keep them charged up