Hi,
testing demo project from SDK RTM 3.0.3 as is on DEVKIT-MPC5748G rev D, it passed the test. I had microSD formatted to FAT32.

Refer to example description and follow the setting stated. Do you have PH8 pin tied low, e.g. setting with setting with OBE: Disabled, PUS: Pull-down, PUE: Enabled, Initial Value: Low?
BR, Petr