I have a 2006 Scion xB that I am having trouble pulling the check engine light code. I know it uses the CAN protocol and the scanner I am using is capable of reading CAN. I also have the VSC, ABS, and TRAC OFF lights on. I am able to pull the codes for the latter though. I understand that they are on different ECUs and have already checked the fuses. These are the codes I pulled from the Skid Control Module: C1223, U0073, U0100, U0123, U0124, and U0126. Because most of these codes relate to communication problems, I've tried to check the MAIN and SUB bus line but am very limited in it's implementation and testing. Please advice on what or how I should diagnose this. I've already replaced the ECM with a brand new one from Toyota.

Cars & Trucks - Scion - xB