Toyota Repair: Toyota 2002 Sienna ABS ECU repair, toyota sienna, different this time

Question
My 2002 Toyota Sienna used to have right automatic sliding door problem, the dealer said we have to replace ECU that cost $2500. I left it like that 5yr back. Last 3 year the Engine light, VSC and Trac Off light all came up once and continue to stay up. The dealer checked for fuel vapor leaks and said ok but the lights came back on. I took to repair shop again for something different, this time the mechanic read the code, the mechanic suspected its loose connection at Transmission solenoid. He traced the problem back to ABS ECU unit. It is not sending right voltage back on several thing including the auto sliding door. He put is back, now ABS light, Brake light, engine light comes up and speedometer and odometer doesn't work. He said we have to replace ABS ECU. Looking for used part, or a place that can repair ABS ECU board. Help.

Answer
Here is what I recommend, take it to a place that can get the diagnostic codes for the check engine light being on, some autoparts stores will do this for you at no charge, let me know what the codes are for the check engine light and we can continue from there.