FWIW: Unsolvable Laserjet III Problem Solved

Archived from groups: comp.periphs.printers (More info?)

A couple of weeks ago I made a post describing how I was long distance
troubleshooting a friend's LJIII with a "50 Service" error and how nothing
that was done helped solve the problem. Those who suggested replacing the
fuser were correct, but it's not a simple story. The short of it is that
what was sold to him as a new fuser wasn't new at all. The thermistor
circuit board was cracked, so while the thermistor measured good at the
solder points the signal wasn't being passed to the connector pins. His old
fuser's thermistor/board appreared to be good so a swap was made and the
printer came to life once again.

Thanks again for your suggestions!