Apple Personal Laserwriter NT "cover open" error

Surely this is not *THE* answer, but ¿have you checked if cover sensor switch has its cables firmly connected?; I don't know if you have access to it, but you can be sure more than once this was the reason a printer reports that error.

I don't have access to the cables.  I can see inside that the cables are firmly wrapped on the left with black plastic, and on the right with protective mesh covering.  I did find a 68M 1/2W resistor on the inside cover where the paper guide is.  It is held by 2 screws that make it easy to remove.  I checked the resistor with my volt meter.  I discovered that the range selector of my voltmeter can only be set to RX10K. Therefore, though I get a high reading at infinity, I can't determine if the resistor is bad, or out of range of measurable resistance.  I am not an expert in measuring resistors.  However, this is my assumption.  Have any ideas?

Thank you very much...Happy holidays!!!

If sensor switch is bad, you can disable it:

a) If sensor does open when cover does, shortcircuit both wires
b) If sensor closes when cover opens, cut a wire to leave circuit always opened.

Thank you VIKIING for the added info.  I have closed this issue, since I no longer see the need to spend money and time in maintaining this printer.  I have decided to go for a color inkjet.  This will be more cost effective for me.  It will also bring me the additional ability to do color printing.  Thank you very much.  I appreciate your input.  Have a Happy New Year!!!

The same for you, Dr.Logic !!!!!!!!!