MY truck is running sluggish, my ABS light is on,how hard is it to fix? on 2000 Ford Explorer

The truck is sluggish, the light is always on. i took it to a mechanic and was told i had to change a some harness and the pump at the same time, costing me over a thousand dollars. At one time i drained the brake system to replace the old brake fluid.

Asked by for the 2000 Ford Explorer
what is the code???? we need this to help you

Thank you for your reply ROY.I didnt get the codes from the mechanics they didn't have them, they said they don't need them. If i go to auto zone or advance auto they tell me if the check engine light is not on they cant tell me what is going on( with all their knowledge?. Dont know what else to do. All i know is that my truck i9s running like the engine is pulling to much weight.