At this point, you need to scan the CAN bus system to see where the failure is. If it was just a light, then I would say a wheel speed sensor is bad. However, since the brakes lock up and you can't turn the vehicle it seems to indicates something different.
CAN stands for computer area network. If you scan the system, it will identify any and all faults. At that point, a determination can be made on what is causing the failure. If you don't, chances are you will keep replacing parts that aren't bad until you hit the right one.
Here is a video showing how it's done:
Ask if he has done that and if he did, ask for the diagnostic trouble codes that were found. Let me know what they are.
Tuesday, August 11th, 2020 AT 3:39 PM