5 Panel Description 2. CHECK Indicator This indicator shows whether an effect is ON/OFF, indicates the tempo (TEMPO mode p. 11–12), and also doubles as the Battery Check indicator. The indicator lights when an effect is ON. * If this indicator goes dim or no longer lights while an effect is ON or while the BF is in TEMPO mode, the battery is near exhaustion and should be replaced immediately. For instructions on changing the batteries, refer to Changing the Battery (p. 14). * The CHECK indicator shows whether the effect is being applied or not, and is used to indicate other effects. It does not indicate whether the power to the device is on or not.