Yeah, that's consistent with the symptoms for a defective ABS Control Module. There are companies that rebuild them or you can replace it. An experienced Volvo tech can verify this in very little time.
When the ABS module fails, it can cause the ABS light and Check Engine Light to illuminate, the speedo to stop working, and the Transmission Light to flash. And the Brake light will come on as well.
This is a very, very common problem with you car, so it's not cheap to fix, but it is very easy to have addressed.
- Bret Bodas