Connector Tweaking

This procedure fixes 51 errors, 52 errors, high-voltage problems and some 50 errors on HP II/III and Apple II printers.
"Tweak" connectors by using a small flat-bladed screwdriver or similar tool.
Close the gap between each pair of contacts about 20%, being careful not to close the gap too much.
See photo below for connector locations.

Connector tweaking at laser scanner assembly.