I am a big fan of the optional XJS (and XJ40) lighted key, not necessarily because of the “torch” light, but because I like the bigger grip key to start the car. The key comes in two parts, the “skeleton” or key itself, and the lighted cartridge.

My XJS key set was stolen recently from inside my X type, and I am having another of these lighted torch keys cut, as I decided to keep the existing locks in the car. I imagine my keys are in the trash or around someone’s neck, and I highly doubt thieves run around with a gigantic key-ring of all their stolen keys to see which one will fit my XJS to drive of into the sunset.

I have several new uncut keys (skeleton) and also 4 “new old stock” cartridges. One of the cartridges, however, already has a perished battery, the others are still operative, but not far behind, I am sure.

I decided to tear into the new inoperative cartridge, to replace the bulb with an LED light. This is how I did it:

In addition to the cartridge, you will need

5 mm LED BULB
CR 1632 battery
thin razor to cut the sealed cartridge open

I initially got a 3mm bulb, and got a green one by mistake, but it turns out you can shove a bigger led in there. I got rid of several of the internals, and of course I got a 3v battery to make the LED work, as the original, 625 style is 1.5 v and perished anyway. It could have been more elegant, but it certainly works well and much better than the. Original bulb









First attempt with incorrect 3mm unintended green bulb :


Final product with correct white 5mm bulb.

 

Now of to the dealership to let them violate me by charging 30 dollars to cut the key