Are you sure you that the LED status indicator is blinking three times and pausing?
This indicates battery fault condition, overvoltage or undervoltage.
Otherwise if the LED status indicator is blinking four times and pausing indicates current overload condition (probably a short circuit).
You could measure the voltage on C108 with a DMM (positive leg), you should measure around 13V.
If there is 0V you could measure the voltage on the two terminals of R7 versus ground to understand if there is a shutdown condition due to current overload.
You should measure around 0V on both terminals, otherwise current overload condition occur.
Finally you could check R40 and R41, they are protection resistors which burn in case of persisting short circuit.