Bed and Hot End temps don't look right. Suspecting mainboard

Hello All

I have an Ender 5 Pro.

Trying to isolate fault if it’s the mainboard Or is it both the thermistors on the bed and the hotend.

When I apply power and only connect the display, the mainboard is reporting 53 deg C for the hot end and 3 deg for the bed.

The room temp is 25 deg C.

The mainboard is 4.2.2 and the firmware from Creality website.

The Creality Ender 5 Pro Marlin 2.0.6HW4.2.2BLTouch

I am wondering if there is no thermistor connected to the mainboard how come it’s reporting 52 ?

Need help. Do I have a mainboard that’s bad? Or both the thermistors have gone bad togeher?

Thanks

Manish.