The Technical Procedures do not make it clear that no message will be returned
if the diagnostics find that the ROMs are OK. The LaserWriter Plus diagnostics
are contained in ROMs H3 and L3 (board locations E7 and F7).
If all the ROMs are OK, nothing will be printed from the diagnostics. If an
error is found, then an error message will appear on the Macintosh screen.
The Technical Procedures are being updated to reflect this fact.