Xerox Phaser 7400 "Close Top Cover"

[Claudio]

Hello evryone:
I have a customer with a Xerox Phaser 7400. She blew out the toner ctg. area with a can of compressed air and now showing "Close Top Cover". I checked and swapped around 2 cover switches with no difference. I warned her she may have a bad logic. Does anybody have any info. as to what may be the problem?
Thanks in advance.
Claudio

[just a tech]

try running the "service diagnostics - top cover interlock test".. if switch is functioning correctly then your engine control board is more than likely bad.....BUT--- if switch tests bad,then replace switch.(which ya did with swapping them around)...SO,if the diagnostics say switch is not functioning correctly AND replacing switch does not fix it , then check the switch voltage on your high voltage power supply..(should have +5 volts CN#2).. if ya don't get ya voltage, then ya need to replace your HVPS.. if ya DO get ya voltage, then ya need to check all pins on the HVOLT harness for continuity..check continuity of HVOLT-11 on ribbon cable..no continuity--replace HVOLT harness..got continuity--check the top cover interlock signal..while checking signal, DISCONNECT the HVOLT from the engine control board...if the voltage changes at HVOLT-11 when the switch is actuated then almost definately it will be your engine control board..AND if the voltage does not change when switch is actuated then it'll most likely be your HVPS.. a whole bunch of shit for one little switch, huh?... LOL...anyways,it ain't quite as bad as it seems.. good luck and hope this helps..

[Claudio]

Phaser 7400

Hello Just a Tech :
Thanks so much for your reply/ help.
I will check these things and see what concludes.
Have a great holiday weekend.
Claduio

[just a tech]

you are welcome..have a good weekend too..

[djwhoo]

Re: Phaser 7400

Hello Just a Tech :
Thanks so much for your reply/ help.
I will check these things and see what concludes.
Have a great holiday weekend.
Claduio

What did you find? What fixed it?