I have a 2000 blazer, I'm having the problem of just as I'm coming to a stop the brakes will cut in and out. I've been told it's probably the speed sensors , but how can I know for sure and how do I known witch side it is? Any help would be great.

 

Its very common for the senors to become corroded and falsely engage the ABS system the best thing you can do is hook it up to a scan tool and see which sensor isnt reading by spinning the tires since they read speed the bad sensor will read incorrectly.

 

^^^ this

had the same issue with mine. used my buddy's scanner at work that could monitor the ABS system and found that I was getting no signal from the front right sensor

contrary to what a lot of people will tell you, you DO NOT have to replace the entire bearing hub assembly just to replace the speed sensor... I replaced the sensor and my ABS light shut off as soon as I started rolling. and to boot, I didn't even use a sensor specifically for my truck, I used one off a mid 2000's full size Chevy truck on my 2004 Blazer 4x4, worked like a charm