Blank screen Having turned the machine on the screen is blank but lit up

I would try the manufacturers web site for advice.

Check that the LCD screen adjustment has not been dimmed or darkened. If that is not the case, then a component is or has most likely failed.

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Sounds like your machine is experiencing a failure of a computer component. Suggest service or, if cost prohibitive, looking for a new machine.

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Most of the time it just needs cleaning.

I would suggest having the sewing machine checked to see if you need a new screen or there is something wrong with the motherboard.

Hi.

On page 81 of your manual it says to adjust your LCD screen brightness.

If you can't find your manual... go here and download it.
http://www.brother-usa.com/ModelDocuments/Consumer/Users%20Manual/UM_PE_770%20%20%E2%80%93%20New!_EN_1819.PDF

There is a small wheel below the buttons on the right hand side that can be turned "up" or "down" to see the electronic letters properly. Sometimes that gets bumped accidentally and the screen appears to go blank - it's still there, just needs to have the letters darkened - they are just washed out. Turn the little wheel and it should return. If that doesn't work, quite possibly there is something else going on. If you can stitch even without seeing the screen - that most likely is the answer. Good luck! S

look 3 inch under left side of screen is a wheel to adjust the brightness

Definatly it is an electronic issue. Have the cables checked to be sure there weren't any pinched between the covers etc. And that the plugs on them are seated properly. This they should do naturally. I have also seen this before when what is called the EEPROM chip went bad. Screen lit, no info. The EEPROM is a small chip, black and rectangular on the S-Print board,The EEPROM stores all the information for the machine to work. The screen will light but no info on the screen if its bad. Before replacing a whole circuitboard I would suggest replacing this. It just plugs and unplugs from the S-Print and much less expensive.
If your not feeling all that trustworthy if the tech can do it then ask that it be sent to Bernina in Illinois and repaired. It could take 6 weeks though.

you may have loose wiring or perhaps the board has had it and needs replacing i recommend repairing from a professional tec should not cost any more than $50 to fix