Caps Lock LED mod for classic keyboard on x230 (and probably xx30) This guide assumes you already have a classic keyboard modified to fit in an x230, the guide will only explain how to add the caps lock LED. If you have not already modified the classic keyboard, follow this guide: https://www.instructables.com/id/ThinkPad-T430T430sX230-Classic-Keyboard-Mod/ Required Hardware: • Thin electrically conductive tape (e.g. copper (recommended) or aluminium tape) • Non-conductive tape • Mini-PCIe to USB adaptor, like https://www.aliexpress.com/item/32848143941.html. This may also be possible with the Bluetooth port to USB adaptor (https://www.aliexpress.com/item/32994301909.html) but the Arduino (probably) wouldn’t fit there, so you would have to use a USB extension or something. • Small Arduino that will fit in laptop, I used a beetle board like thishttps://www.aliexpress.com/item/4000998266298.html • About 20cm of thin, insulated wire • NPN transistor, I used a 2sc1815 Steps Remove the keyboard and palm rest by removing the labelled screws on the back of the device. Steps in this guide: https://imgur.com/a/fsRe6 to get to the internal ribbon cable. Add a large piece of non-conductive tape around the edge of the keyboard under this pin, so that the conductive tape in the next step does not short into the body. On the same side as you would add tape for the normal mod, add thin non-conductive tape over the pin shown in red. This pin is the negative caps lock led connector. We will bring this to ground when we want to turn on the LED. The blue section shows the pins you would tape over in the normal mod. The result is this: Now cut a small piece of conductive tape to put over the isolation so we can access the pin. I made it in the shape bellow but connecting this tape to the wire was very difficult. I would recommend a design more like what can be seen on the left, so that there is more area to attach the cable to. I would also use copper tape so that you can solder the cable onto it. Apple this tape onto the pin, and then wrap the tape around the ribbon cable, as shown: Carefully put the ribbon cable back into place, Screw the two panels back on. Strip the end of the wire and wrap the conducive (non-sticky) side the aluminium tape around this. Make sure the connection is reasonably secure and makes an electrical connection. This isn’t a very good way of securing the wire. Perhaps it could be crimped, or soldered if copper tape was used. I then added heat shrink and some epoxy in a desperate attempt to make the connection hold Now leave the epoxy to cure. We will now start on the Arduino. I am using a beetle board, as it is the smallest Arduino I had. Solder an NPN transistor to the board (I used a 2sc1815), solder the emitter to ground and the base to a digital pin (in my case D9). If you use a different pin then you will have to change the pin number in the code. You can find which pin is what on the datasheet for the transistor. Load the program onto the Arduino using the Arduino IDE, in the case of the beetle board, set the board type to ‘leonardo’. Plug the Arduino into the computer and click the upload button (the arrow pointing right on the top). Now solder the wire from the keyboard to the remaining leg of the transistor. We will heat shrink over this, so remember to put the heat shrink on the cable before soldering! Add some hot glue to secure the transistor and insulate the pins. The Arduino is slightly too wide to fit in the mini-PCIE to USB adaptor So I ground away some of the pcb with a Dremel, so that the board would fit Secure the Arduino in place with some more hot glue Put this into the computer, making sure the Wi-Fi antenna cables don’t come off the Wi-Fi card. Route the extra cable where the blue and black antenna cables go (so that the cable can go under the palm rest) The caps lock LED should now work! If it doesn’t, make sure that wwan is enabled in the BIOS. If it still doesn’t work, either the Arduino is broken or your cable/pin to the keyboard isn’t making a connection, check the connection from the conductive tape pin to the wire.