Disassemble the code with IDA Pro and see.

If this is beyond your skill level, then trial and error.

me7info.exe from the me7logger can sometimes help. Otherwise ida. I uploaded a reasonably complete me7.1.1 st10 ida project on here somewhere . Yours isnt st10 but  much c167 me7.1.1 looks similar. once you find code that uses the variable in mine, you can search your bin with a hex editor. Mask off all addresses when you search as you are looking for similar code but referring to different addresses, or search for nearby code that looks unique. It takes time and patience but at least you will know the code that is using the ram address in question and can look for it. To avoid such nuisances, you need an a2l file for your bin, its worth your weight in gold.