Recently I bought my first MINI - a 2003 MCS 6MT. I looked at several cars before I settled on this one.

There was one common theme I noticed with each car I looked at - every single keyfob looked completely destroyed. Few worked at all, and a couple would only lock or unlock the car. I have yet to have one in my hand that was completely intact.

Generally, they looked something like this:


A few things missing here...

See that little silver rectangle with the polka dot in the lock button hole? That's the actual tactile switch, and there should be 2. The second should be between the solder tabs in the unlock button hole.

Mine looked very similar to that picture; the lock switch was there, and unlock was missing completely. Sometimes the lock button would work, but usually not.

So I popped the circuit board out of the key and did some electrical testing.. because that's what I do. The battery wasn't dead, and I found that if I jumped across the terminals on either button the little red LED would light up. So the electronics still worked, I just needed new switches. I confirmed this by jumping the contacts while I was near the car and it worked perfectly.

After some searching I was able to find suitable replacement switches. There was a little guesswork involved, but I landed close enough. If I were to choose again, I'd go with the 4.5 Newton (how much force it takes to push the button) switch instead of the 2 Newton. I bought the silver contact version, because it appears that's what they were originally and corrosion didn't seem to be a problem.

Here are the switch parts if you need them; I bought the Silver contact 2 Newton ones.

Gold, 4.5N: https://www.mouser.ca/ProductDetail/611-KSR253G-LFG
Silver, 2N: https://www.mouser.ca/ProductDetail/611-KSR221G-LFS

Once you have the switches in hand, all you have to do is remove the old one(s) if present, clean up the board and carefully solder on the new ones. They are pretty small, so it's a bit fiddly and you'll want to be careful about how much heat you put to them. Orientation doesn't matter - either way around will work. You'll need a decent soldering iron with a nice fine tip, and limit the caffeine intake so you're not too jittery.

When you're done, it should look a bit more like this:


2 switches installed, and spares on the side.

That just leaves the keyfob case itself to be replaced. These are available through Amazon, Ebay and likely other places; mine is on the way, but still a couple weeks out. I'll follow this post up with how to do that swap when it arrives.