PSR 8000 Problems

[PSRPETE]

Hi Guys and Gals,
I haven't visited much over the last year, (except to learn more about arranger functions in general; thanks to everyone 🙏🏾👍🏾, especially Joe for his site administration!!! 👏🏾👏🏾👏🏾), but now I'm here to ask for insight and advice from those that have repaired a keyboard, (especially those that may have worked on a PSR 8000).  I know it's a long shot, but here goes:
I replaced 3 keys and springs that were damaged.  I reassembled the board, turned it over and on.  I then discovered that the lcd, (which was working just fine beforehand), now is lit and flickers but no text or images display.  Also, the speakers hum and sound only up to half of the keyboard's max volume.  If I turn it past that, the sound diminishes to barely audible and the hum increases in volume.  I know it's my fault 😩 because before the keyboard worked perfectly, except for the broken keys.  I guess my general electronics question is:  is it possible that there's a simple solution to my problems?  I was very careful, didn't damage any connections or terminals, reassembled the keyboard referencing pics I took during disassembly, and took my time every step of the way.  I love this keyboard and it's features, but I'm thinking I may have to put it out to pasture.  The speaker problem doesn't worry me as much as the lcd problem just because specific parts for this keyboard are hard to find, (especially lcd's).  I hadn't really gotten familiar with it's features yet either.  The good thing, (if there is any), is the keys work perfectly now.  😂
Thanks for your help with this quandry. 
Pete

[overover]

Hi PSRPETE,

It is possible that "only" an internal cable (connector) is loose or incorrectly plugged in, but first I recommend to do the following (if you can see something on the display):

If you don't have the PSR-8000 Service Manual yet, you can download it here:
>>> yamaha_psr-8000_sm.pdf

I would first start the PSR-8000 in TEST mode and, if necessary, run all Test routines that do not require external measuring devices. This may give you clues to the error(s). Information on the internal TEST program can be found in the Service Manual from page 38.

If the display cannot be used at the moment, I would open the 8000 case again and check all internal connections/cables again.


I hope my tips will help you!


Best regards,
Chris

[PSRPETE]

Chris,
Thanks for your help with this!  I do have the service manual, but I can't read the screen.  I will consult the manual and do what you suggest.  You give me hope!  👏🏾🙏🏾. I'll post my findings tomorrow. 
Pete

[PSRPETE]

Chris,
You rock!  I connected a right angled cable on the pcb board rather than on the case of the DM board and it caused both problems.  I'm glad I didn't short something out.  I missed it because the pics I took don't lie 😳😂.  Thanks again Chris!
Pete

[wersianer]

Pete, Chris is a pearl, many others and I have already experienced that.

[PSRPETE]

Pete, Chris is a pearl, many others and I have already experienced that.

I agree wersianer!  What is more, this community is a pearl as well.  I can't tell you, (or anyone), how much this forum has demystified the concepts behind playing an arranger keyboard.  Personally, I love the blend of tech and playing - all on the fly!  Thanks to everyone who has posted something I've seen since joining.  It has been interesting to read and has or will benefit me someday.  Cheers!

[overover]

I am very happy that your PSR-8000 is working again, Pete!

Thank you (and also wersianer) for your kind words!


Best regards,
Chris