Side cover open

The Exit 2 interlock switch is either broken or off it's base or defective. If you open up the top door on left side of print, there is a push button switch that mounts on the back side. If you're standing on the left side of printer it's located on the top left. Make sure it's mounted properly and try to push the button with your finger and see if error goes away, if not replace switch, part number 110E11580.

http://www.iteminconline.com/110e11580_xerox-5500-door-b-interlock-switch.htm

1st Side cover is front cover.The cover which you use to open to install or check toner bottle.When you close that cover and machine gives caution then it means cover is not properly closed
"OR"
The 1st side cover switch is not working properly.
There is a knob at the end of the front cover, make sure it it aligned with the switch.
Front cover Micro Switch can be dirty due to toner spilling/dropping inside the machine.Clean it and then recheck.

Open the drivers side door and see if you can peel back the covering on the wires going into the door. Sometimes from opening and closing the door so much 1 or more of the wires break or rub bear and contact each other or something else. Check if all the wires are good.

Check the switch just inside the door. If it's not chiming, it may not be switching the fan either.

there is a switch at the side that is being push by the cover when it closes check this switch to be sure it hits the button when close or you may replace the switch it has a problem.

Chances are its a door switch or the wiring close to it. the wires bend every time you open and close the door. Check for that but if your dead set on a relay. look under the hood you should find a relay panel on the left(drivers side) finder well. On the cover of the panel box will be a listing and placement for all the relays

Dear, open the duplex cover, at right corner inner side of duplex cover,there is a micro switch which is not getting pressed,see weather duplex cover is completely closing,If copying is going on see the duplex cover is slightly getting open,if so press the duplex cover while copying is don, for confirmation that switch is not activated.

Regards
Mahaboob Basha.T
Bellary
Karnataka
India

Look at either side of the flip-up cover. While I am not familiar with Lexmark printers, I have seen this problem in the HP 6800 & 6900 series. There should be on one side (my guess would be closest to the 'rest' position of the ink carriage) some sort of switch to detect cover position. In the HP printers, the switch is 'down' when the cover is open; so, if the little lever that would lift the switch to the 'up/closed' position if broken, the switch stays in the down position and the printer thinks the cover is open. Look for something along these lines.

The door switch has gone bad or is intermittent. replace the door switch located at the top of the door at the hinges.

sounds as if your fan motor is hitting on something most likely ice. the fan cuts off and on when the door is opened. the easist fix is to defrost the unit manually by unloading all food and unplugging the unit for several hours. if yo arent in a position to do this it will require removing coil covers to gain access to the fan and remove the ice manually. good luck peyton