openecu.org

im currently using ecuflash 1.43.3150b beta and using the mitsubootloader to work with colts and lancer ralliarts. I can read the rom fine and upload it to the computer but when attempting to change any info in the rom within ecuflash or any external hex editor the checksum changes and once reflashed to the ecu a flashing check engine light occurs with an internal memory checksum issue. The actual rom data itself is changed and works(tested by changing init code and seeing if it changed in ecu) but there is issue of checksum. Tried in normal mode, recovery mode and benched ecu. modules used are mitsubootloader and mitsucan. In disassembly the checksum sub routine can be found for the reference points but its painstaking to have to find each segment. The evox runs the 32196 proc from memory so how does ecuflash overcome this issue in the evox? I had assumed it was using a very similar bootloader but with the options to enter and exit programming states etc. Can anyone explain how ecuflash circumvents this issue with the x's and could it be applied to the 32176?

Cheers

Without knowing the details myself, I'd imagine that the code itself checks the ROM checksums. You either find the code that does the check and bypass it, or find the checksum tables or secret values and hack them. You can't really get around it otherwise; it's meant to detect an invalid ROM, which it is in this case (as far as it's concerned). The method of flashing is irrelevant.