Hi @Andrew101,
S32K144 UART example from RTD uses UART0 and FlexIO to test communication:

You can scope these pins to see the transmission. Or you can wait for the example to compare verify the transmissions. From the description.txt file:
- The first welcome message is sent via UART: "Hello, This message is sent via Uart!"
- The second welcome message is sent via UART: "Have a nice day!"
- User need to check return status of Send_Data() function for verifying example.

It uses Lpuart instance 0, comunicates with Flexio instance 0 channel 0 for Rx and channel 1 for Tx (connect PTC3 (J4.16) - PTD2(D6)(J6.3) and PTB0 (J4.5) - PTE5(D7)(J6.18)).
Best regards,
Julián