Boss GT-6B multiple guitar effects pedal board, 2005

Not a stuck sw problem. Unlikely rotary encoder sw problem as physically rotating it changes the 7-segment display but the auto scrolling error function does not. No susceptibility to touching components. Select a funtion like tuner and the display stops scrolling and gives tuner display. Disconnecting all ribbons except the display one , the scrolling display still there so a main board problem seemingly. I suppose ESR caps check is first port of call. User manual from Bossus site and schema etc on e-service

I never had any problems with my GT6. Used it to gig with from 06 to 08.

I asked, at receipt, whether this one had been connected to a pc and it had not. I've just asked whether it had been connected to a sequencer and so maybe the other one had as well, transferring corrupted code. This 6B same as the e-service 6 pdf as far as display is concerned , buffers between uC and display seem to be operating correctly but still scrolling with the switch and rotary board disconnected. No obvious ESR problems, little much else to do, check a few V if 6 and 6B agree there.

With all ribbons disconnected other than display one I noticed that the display stabilised if "digital" fingering of the empty mainboard socket for the ribbon that goes to the sw board and pair of analogue mx chips. Reconnecting that ribbon the display still scrolled but tugging on the fixed end of the ribbon stopped it. Resoldered the ends and display and overall functioning seems normal, eg up/down bank buttons function, unlike before. Nothing obviously wrong with solder or the crimp? terminals to the wires that are also the solder points but something wrong there. Not PbF but resoldered all 4 such ribbon fixed ends JIC. As maybe generic Boss problem area they are no-name white "Harwin" 0.1 inch type connector system for discrete wire ribbons, same crimp? system at the fixed end (inserted into the housing then soldered to pcb) and socket end , so standard sockets at one end and solderable thru-housing and pcb pins at the other. So is it coincidence the other one was playing up the same way and was genuinly cured by factory reset or same wiring problem coincidently disappeared for the present on that one? Or of course some other intermittant problem with this one coincident to fiddling with one connector, the repairman's dilemma. Repairing (or not) by divination in effect.

I've now had word back that both units have only been connected analogue to amps and guitars, no midi or digital connections. Not bought from same supplier either.

Well the 6B must have had a USB port if you are talking PC connections. Mine had no USB. I don't recall if you could upload new patches using MIDI as I never did.

My 6 suffered road abuse. Was dinged and dented but never failed. Just an FYI. Don't think those problems were endemic to the 6 unless their were changes made to the 6B.

Phone Roland Service dept, and speak to a person. If it is a common fault they will know about it.

Gareth.

After making sure, of course, it isn't a power supply issue..