These commands show a simple use of UINT16_MAX, then build it so the preprocessor listing file is created.

% type file.c
#include <stdint.h>
uint16_t var = UINT16_MAX;

% cl2000 --gen_preprocessor_listing file.c

Inspect the last two lines of file.rl to see ...

Nuint16_t var = UINT16_MAX;
Xuint16_t var = 0xffff;

Because the constant 0xffff is not suffixed with u, it fails MISRA checks.

Other UINTnn_MAX macros have the same problem.