I've been trying to resurrect a Toshiba T2130CT laptop and it's proving tougher than I would have hoped. This is replacement motherboard #2 and until a few minutes ago, it was broken. Troubleshooting a laptop motherboard wasn't what I wanted to do but getting replacement parts means even more waiting.
I'd seen a blog post here a while back about the Toshiba LED code reader that connects into the parallel port: https://nielssp.dk/2019/09/fixing-410cdt/
So I made my own, can't find schematics but it's pretty simple to put together, just connect some LEDs to pins D0 to D7 on the parallel port. I used 150 ohm resistors so they wouldn't burn out and then covered it all in hot glue. Now I've got a special Toshiba password removal dongle and this post code reader dongle.
In action it blinks through some codes as a binary counter:
On my dead Toshiba T21xx board it was doing still nothing and I was gonna give up and contact the seller to get another one. It would just light up all the LEDs at once.
Poking around I found that the biggest chip on the board, a QFP-240 had some loose pins that I tried resoldering by hand under the scope, but it still didn't boot. As a last ditch effort I went over the CPU, the RAM, all the big QFPs on the underside of the board with my Quick 861DA hot air station at 330c for a while. That worked? I didn't expect that to work! Being able to see the post codes on a laptop is really handy and I can see myself using this dongle in future potentially.
I'm a bit disappointed since I bought this board as tested and working, but the last board I bought (that was refunded) was also sold as working and had tons of visible corrosion and battery damage. The one I'm using here I think must have taken a knock to the middle of the board either in storage or during shipping, I'm really glad it works now though.
I'm running it on my bench PSU instead of the built-in mains PSU, but still at the voltage that PSU was running at which was 18.3v. It only uses 500ma when running with this DX2-50 and it'll be interesting to see how much more power the DX4-75 uses when I install that on this board 😁
That Toshiba pre-load I mentioned a few days ago, that was on this hard drive appears to somehow be an actual complete pre-loaded hard drive that's not even registered? I'm confused how this could be since the T2130 predates recovery CDs.