I have a '97 f-250 with the rear wheel abs. Both the abs light and the brake warning lights are on. Brake fluid level is good and not leaking anywhere. The brakes work fine, but I can tell the abs is not working, not that the abs worked will in the first place.

I tried unplugging and cleaning the wire connectors near the master cylinder, and took the sensor out of the rear diff. and cleaned it. The lights are still on.

Any Ideas what the problem might be?

Does anyone know how to get trouble codes from this abs system?

I thought about disconnecting the abs and removing the warining bulb from the dash, but the red brake warning light is on also and I would like to have that one working incase I ever loose brake fluid.