99 F250 SD cruise control not working

When I try setting the speed control, the green cruise light comes on but it doesn't hold the throttle. I've changed the pressure switch on the master cylinder. Any ideas?

I was going to suggest the pressure switch since they had a recall on that. If you have a green light, then the electric portion is working. I would guess the cable controller no longer holds the throttle, probably worn out. I've never had to work on one so I can't help with diagnosing or repair hints. (At least not on anything newer than a 1975 pure mechanical)

Thanks for the reply.