EX2100 not start in auto mode

Hi Control.com community,

I'm reaching out for some assistance with a persistent issue I'm facing with an EX2100 excitation system on a power plant unit. The system refuses to start in auto mode, causing operational headaches and requiring manual intervention.

Symptoms:

• When switching the selector switch to "Auto," the EX2100 doesn't initiate the automatic startup sequence. and we detect that start command goes from Mark VI to EX2100 but EX2100 not receiving the Start Command as signal over EGD
• No alarms or fault indications are present on the system panel.
• Manual starting through the "Start" pushbutton works normally, bringing the unit online.