ABS light on

I have been having my ABS light coming on for the past few weeks. Today it came on and stayed on. My speedometer stopped working and I can only drive in second gear. Anyone have any suggestions?:(

My guess is you have a problem with the vehicle speed sensor or it's wiring. The Service Engine Soon light should be on also.

You lost your speedometer which means the IP isn't seeing the signal from the PCM. Your ABS light is on probably due to the fact the PCM isn't receiving the signal from the VSS to send to the IPC or the ABS unit. And lastly since the PCM isn;t seeing the signal it went into default or "safe" mode and wont let the trans shift preventing further damage. It has no idea if you are doing 10 mph or 100 mph so it defaults to second or third gear.
I hope I didnt confuse you but it's probably just a simple repair.

Schematic

Location..although this is a generic pic.

How Do you Fix it....

How Do you Fix it....
Took the Blazer to my chevy dealer and they replaced the speed sensor. It actually had a crack in it. I has been fine ever since.
See BOWTIEBANDIT's reply to my original question he was completely acurate. Good luck.