A damage 919-4212 DC Regulator will lead to this red LEDs. The DC Regulator Board has an input +48Vdc voltage coming from the Mean Well Power Supply, check the F1 Fuse. If this voltage is present in the board then its necessary to check for all the lower dc voltage values +5Vdc, +12Vdc, -12Vdc which feed the CPE Board (Controller Plus Exciter) and the Front Panel Board. Also check for visual damage such as Q1 & Q2 MOSFETs or any other components.
On J1 Connector which is the voltage supply to CPE Board, check the following voltage levels;
Pin 1 = +5Vdc
Pin 5 = -12Vdc
Pin 6 = +12Vdc