Mark VI RPSM Red light indicator

Good morning Dear forum colleague and my honourable experienced engineer.
I have a question regarding RPSM Red indicator light was permanently ON suddenly we met it like that buh our observations was the temperature of MCC Room wasn't friendly. It TMR controller system where we have RST so rack S PSM red light is ON after a while the AC was put on afterwards buh hoping to see if the red light will changes back to green Which is the usual light.

I'll be glad to know about this and how rectify this fault.