ADVICE about fixing a DEAD ROLAND VG99

Started by cubasevst, June 23, 2021, 10:46:14 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

cubasevst

hello to anyone who got such a problem...
i own 2 vg99, one for live playing and another rackmounted in my studio. the one i use for live had problems with almost every rotary button (6 ones under the screen) plus random contacts of F buttons right under rotaries. So very carefully, i decided to open my vg99
(even if i m not an electronic engineer, electronics and max/msp software programming are one of my hobbies). everything went fine. i used my cleaning spray (not air, but one that disolves microdust without leaving moisture). in one of the pictures, i drew an arrow where to spray since the rotaries are hard to access in. A couple of short sprays and i turned many times clockwise and counterclockwise until it could turn fluently. Same thing for buttons. Short spray on it and i kind of pressed it on off plus moved it in some sort of "Freddy King guitar string vibrato ;D ;D ;D". i let the board dry for a couple of hours in case of, remount everything, plugged all the cables, fixed the screws and finally, turned it on....AND.........DEAD......
I UNSCREWED, UNMOUNT, CHECKED EVERYTHING, REMOUNT, REPLUG, TURN ON AND.....DEAD.
I bought this second VG99 second hand supposedly good conditions BUT since first day, screens appeared randomly in the main display due for sure to dirty rotary and buttons that with use, got worse. When i opened it, it s been obviously already opened in the past and the original owner mounted it back badly since screws were missing and one of the copper shield too.

to resume, if one day you need to clean rotaries or buttons, no problem. BE CAUTIOUS! ONCE EVERYTHING IS PLUGGED, SCREWED, CLOSED AND YOU TURN IT ON AND....DEAD, THE TRICK IS THAT WHEN YOU PUT THE 2 WHITE FLAT CABLES BACK INTO THE SLOTS (THE ONES ON THE RIGHT OF MAIN BOARD THAT GO TO THE ROTARIES AND BUTTONS BOARD) MAKE SURE THAT THEY ARE PERFECTLY SLOTTED.
IF THE ONE CLOSER TO THE EDGE IS BADLY PLUGGED, THE UNIT SIMPLY WON T TURN ON...AT ALL.
IN MY CASE, THE OWNER PUT IT BACK BADLY AND BROKE A COUPLE OF CONTACTS SO I HAD TO CUT THAT PART, 1 MILIMETER, PEEL THE CABLE, MADE SURE THAT EVERY CONTACT WAS IN GOOD CONDITION USING A MULTIMETER AND CHECKING THEM USING A WATCH REPAIRSHOP MAGNIFIER. (THE PART OF THE CABLE THAT I CUT IS IN ONE OF THE PICTURES).
SO I PLUGGED IT CAREFULLY, CLOSED EVERYTHING, PLUGGED AND .....HURRAAAAAAHHHHH
BABY IS BACK.
I hope this 2 days nightmare can be usefull to any of you guys. LONG LIVE VG99 !

admin

#1
Always take pics of the unit under repair, prior to disassembly, or removal if any cables. Use same pics as reference during reassembly.

And review the Service Manual
https://www.vguitarforums.com/smf/index.php?action=dlattach;topic=28.0;attach=965

cubasevst

Hello
Thanks for your reply. Of course i took pictures.the problem was that the original owner for sure tried to fix the rotaries problem opening the vg99 and  plugged back the white ruban cables using either boxing gloves or his feet because as you can see in one of the pictures, the stripe i cut has 2 contacts folded and the right edge kind of broken. That cable, instead of being rigid like the other one, looked like an accordion. So obviously, It couldn t resist another unplugging . I was lucky enough to fix it cutting it because i don t think finding that cable is an easy thing.
One of my gks is mounted on a klein headless guitar. Another is mounted in a strat type body only for midi, strung E-A-D (one octave highier to reduce pitch to midi conversion delay) -G-B-E. The vg is a wonderfull machine whose purpose, for me, is not only to emulate so many guitars, fx and amps but to design impossible instruments using impossible tunings too. An incredible creative tool.
My only critic would be the midi conversion. I still own an axon ax100 and thought vg could replace it so i don t need to carry  so much weight...but.....i didn t get same results. I would have liked more midi options in last firmware but....nothing.

mooncaine

You opened your VG-99... and you fixed it....
You are a hero to me. Thank you so much for documenting what you saw and sharing what you learned.

cubasevst

Hello mooncaine...
Fixing it was really expensive and would have taken long to. So i had to try myself. If not, no gigs, that means no money. What happened to yours?

mooncaine

Nothing happened to mine... Yet. But since it's the most important piece of gear in my rig, and since the few gigs that I get seem to benefit from me being able to produce almost any guitarsound in a moments notice...


I like to know all I can about keeping these things healthy, happy and on the job.

map747

Can anyone help me with pictures where the little springs go? Apparently they serve as grounds between the boards. My unit is dead and i can't tell exactly where they go from the pix in the service manual.