Hardware problems with OLPC XO-1: my 2 cents

Problem: my kid's XO wouldn't turn on. The power light would go on, but the screen would stay dark. And it wasn't just the backlight. There was no startup sound as well. Powering on while holding D-pad left did start the hardware diagnostics, but the machine turned off in the middle of the test and wouldn't come back up.

On the OLPC wiki I found excellent information on startup diagnosis, but my symptoms weren't there. The next step was to use the excellent disassembly instructions and look for a connection shaken loose or some mechanical damage.

XO is really beautiful inside. Looks very sturdy, also it looks simple and sophisticated at the same time. Mostly everything is in the top part, behind the screen. There are only ~9 wires coming from the bottom: 2 from the battery, another small 2 wire connector (battery temperature sensor or something like that) and a 5-wire keyboard cable. It took me a minute or two to identify the problem.

Solution: remove the 2 cents coin from the SD card slot!

P.S. Also, I checked out the firmware easter egg (power up while holding D-pad right). Nice!