i had the same problem once on a sierra i had changed the alternator,battery etc and the battery light was still on
i then called out an auto electrician out and he suggested i take the cowling off from around the steering wheel and where the wiring runs down from the ignition it goes down to a connector plug which sometimes can have a crap connection over time.
he then told me to cut the wires off from both sides of the plug and reconect them using a new connection box and it worked a treat.
I dont know if its the same on the escort and i wouldnt cut the wires before having someone who knows look at it but it might be worth taking the cowling off and see if the wires run down to a connection plug and give them a wiggle see if it makes a difference hope this helps