Hi @NJ_NXP,
1.
If you are using RTD drivers, refer to the Integration Manual for the S32K1/S32M24x FLS Driver (RTD_FLS_IM.pdf), specifically Section 10.4.1 – ECC Management on Internal Flash.
The document can be found in the RTD installation directory, for example for RTD 3.0.0_QLP02:
SW32K1_S32M24x_RTD_4.4_3.0.0_QLP02\eclipse\plugins\Fls_TS_T40D2M30I0R0\doc\
Regarding FlexRAM, it does not implement ECC. However, if a double-bit error is detected during a copy-down operation, the EEPROM record is read as all 1s.
For more details, see application note AN11983 – Using the S32K1xx EEPROM Functionality:
https://www.nxp.com/docs/en/application-note/AN11983.pdf

2.
The fault can be emulated in the flash controller by setting the FERCNFG[FDFD] bit and then performing a flash read.
Alternatively, the fault can be generated by reprogramming an already programmed flash phrase and subsequently reading it.
Regards,
Daniel