Printer Lexmark x3470 showing "Cover open" / "Cub abierta" while closed, problem!

Start with checking the brake light switch.
follow the brake pedal up the metal arm until you see a little switch pressed against the metal arm.
When the brakes are pressed, the switch button extends and unlocks the shift lever and turns on the brake lights.
It is common for a little plastic piece to deteriorate and break away, causing the brake lights to stay on and can damage the shift lock solenoid.
Attached is a photo of the brake switch where it contacts the pedal arm.

There is a little snap cover beside the shifter. You can pry it open with a little flathead screwdriver and insert a thin object inside to release the shift lock and get out of gear until you find the fix.

For a number of years, automakers have used a "standard" type of brake light switch set-up.
That is, they put a plastic switch in a metal or plastic holder above the brake pedal arm under the dashboard, so that when the driver pushes their foot on the brake pedal, the arm goes toward the floor, and the brake light switch is "closed", (the plunger in the switch extends) allowing the current to flow to the brake lights.
Common problems then, are:
The plastic switch comes out of the holder, allowing the push button to extend, and keeping the brake lights lit.
Or, the switch fails, same as above.
Or the plastic stopper on the brake arm fails, again causing the plunger to stay extended.
Find a tiny person to stick their head under the dashboard, and you should see the problem.
God bless your efforts.

It is a common fail in this model there is a plastic arm which works as an extender for the switch that senses that the cover is open this part is easily detached from its place(in my case not broken but it could happen I suppose) resulting in printer showing that message. the switch is situated under the the scanner in the middle . when you lift the scanner part to see the ink cartridge, you see a plastic part underneath that looks like a 2/3 of a circle that is the part that pushes the switch. 
You should open the printers gut and place the loose part back in place. Be ware that flat cables contact ends could easily brake use caution. (if you shake your printer you may hear the sound of the lose part).

You may ask if you need further assist.
and PLZ rate!

Happy solving problems!
Bruce