Vertical movement is abnormal
I would check the KGTSP power board. There are a few relays on that board that can go bad. I've always replaced the board but you can try cleaning the relays.
Let me know how it goes.
Best of luck!
I have replaced the GTSA board with a new one, put in a new battery and done all couch calibrations to zero position, however it still seems that it only allows me to go all the way up above the 0 position and when I try to lower it down it jams at 005 and wont go any lower, also the bed horizontal movements are grey out and not possible.
Also the GTSA boots up okay but just wont allow me to go lower beyond the 0 point and no horizontal movements.
Check the couch vertical encoder string and horizontal photodiode sensors.
But I still recommend checking KGTPs power board.
And since you replaced the GTS board and the battery make sure the 'Zero Adjustment' was done properly.