PROBLEM DESCRIPTION #1: The ImageWriter printer carriage
assembly freezes or grinds when connected to a Macintosh or Apple
II Super Serial card.
BEFORE YOU START: Familiarize yourself with the ImageWriter
Technical Procedures.
CAUSE: One or more of the carriage drive transistors is
defective or one or more of the insulators is cracked or broken.
CURE: Remove the string of carriage transistors from the
ImageWriter referencing the technical procedures if needed. Check
to make sure that none of the insulators is missing. Each
transistor should have a mylar insulator between it and the
printer chassis. An insulator for the screw should also be
present. Install new insulators if any are missing or cracked.
Reassemble the printer and run the printer self-test.
In the event that all insulators are in good condition then
replace the string of carriage transistors. ALWAYS REMEMBER TO
REINSTALL ALL INSULATORS WHEN THE CARRIAGE TRANSISTORS ARE
REPLACED. REMEMBER THAT THE PRINTER WILL EXHIBIT THE SAME
SYMPTOMS IF THE INSULATORS ARE MISSING. (A TRANSISTOR SHORTED TO
GROUND.)
Run an extensive self test on the printer. Sometimes the CPU
board will cause transistor(s) to fail again. In the event that
this occurs, replace the CPU board and the transistor assembly.
PROBLEM DESCRIPTION #2: The Carriage Assembly stops or vibrates
when powered on and the printer IS NOT connected to a computer.
CAUSE: Occasionally, one of the transistor wires is cold-soldered
to the transistor itself.
CURE: Replace the string of carriage transistors.