Pixhawk4 board not giving +5v to the UART ports

Hi,

I’ve been working on a drone project using Pixhawk4 as the fcu, but recently I’ve started encountering this issue where half of the ports have stopped working (I have checked ports Telem2, GPS and UART/I2C port were not functioning).

When a sensor or GPS is connected to these ports, the sensors are not powering up and also not receiving/transferring any data. I am sure the sensors and the GPS module is not faulty as it is working on other Pixhawk4 board.

Weirdly, while further diagnosing I found that that the GPS, telem2 and UART ports are not receiving +5V, when I checked with with a multi-meter.
Even after removing the GPS unit (or other sensors) individually the ports are not working.

I currently have the Pixhawk4 FCU powered by the PM07 PDB, and other modules include benewake tfmini at telem2, holybro GPS to GPS port, px4flow sensor to I2C, holybro telemetry to telem1, and rc receiver to the PPM port.

Thanks