Hi there, I did my brakes myself and had the same issue on my GS430. It gave exactly the same errors. I too did not know I had to disconnect my battery but will be doing next time.
To fix this, I put one small copper wire that connected to the top 4th hole from the left and the bottom 5th hole from the left of the OBD2 port. After it is connected, put the ignition on and the brake lights will start to flash. Immediately press the brake pedal 8 times and that within 5 seconds. Make sure to press in and out properly so the lights go on and off. It didn't work the first time I tried it, I gave up and tried next day and everything cleared and has been working since!
I don't know if you've already fixed them but for anyone else that has this issue after doing the brakes themselves, make sure to give this a try as it definitely worked for me.