abs light off and on

I own a a 96 Blazer and the abs light keeps coming off and on and stays on sometimes and does not come on at all sometimes.I check everything that i possibly can No brake problems could it be a malfunction with the light or one of the sensors bad? also Drivers seat
handle for reclining broke off (shaft broke I drill out the old shaft and placed a solid bolt inside to hold the seat up so I could drive.any solutions

my 92 blazers abs also went out. Do u ever go over 70 and try to stop? if it makes a real loud whinning noise and your brakes dont stop the truck its ur abs box is faul. they had a recall on this back in 92 but for some reason my truck dont qualify for a recall. go figure. well sorry i couldn't be any more help.