Unit is from '95. There are no switches sensors or wires in the area of lock or the pedal-- just a mechanical cable operation between the two.. It only happens when you have to push real hard on the pedal to release the lock. The pedal makes a hard contact to the deck at that point. Then when you try to pull out of the pallet, it throws the code 53 and shuts down. The real question is what is code 53? If I new that I would know where to start. Any help is appreciated.