If you can't clear them, it most likely means they're current. ABS. codes usually "clear" when you shut the car off. The codes are still there, but typically the light will go out unless it's actively seeing an issue.
C0035 indicates an issue with the speed sensor. That's generally pretty straight-forward. Either the sensor is bad, cannot read the hub, or cannot communicate with the module. Check wires and connectors. If all is good there, suspect the hub.
C0896/8 are voltage/power supply codes for the module. I'd start by finding a wiring diagram and check the wires with a meter. You're looking for the 12v power supply, and the - Ground circuit.
