GT-1: It won't power on.

If your GT-1 doesn't power on, please check the following points:

• Power Supply
  • Use brand-new dry alkaline batteries (AA, LR6) x 4, or specified AC adapter/power supply*
    (sold separately, BOSS PSA series).
    *Do not use any other AC power supply, which may cause temporary or permanent malfunction.
    Note: Using a 3rd party other brand power supply will void all warranty terms.
    
    
• While batteries or power supply are connected.
  Connect a guitar via 1/4" TS mono unbalanced instrument cable, like our BIC/BOSS Instrument Cables, to the INPUT jack of the GT-1, to power on the unit.
  
  • The INPUT jack doubles as the power on/off switch.
    Power to the unit is turned on when you plug in a cable to the INPUT jack; the power is turned off when the cable is unplugged.
  • If necessary test and check, using an alternate 1/4" TS mono unbalanced guitar cable.