Checking batteries – Sony HVL-MT24AM User Manual
HVL-MT24AM_GB 2-889-493-01 (1)
lamp on the control panel comes on or blinks when the batteries are low.
Changing the batteries is
recommended. The flash can still be
used in this state if (Flash-ready
lamp) on the rear of the unit is lit.
Flash cannot be used.
Insert new batteries.
If nothing comes on when the flash ON/OFF button of the macro flash
controller is pressed, check the orientation of the batteries.