E40 checksum error

I'm new to efilive and am working with a 2005 corvette. I have previously applied the MAF OS patch successfully and recently made changes to the calibration and tried to flash the new cal file but received a checksum error $06FF. I've tried flashing the original cal file and the one read off the PCM after the MAF patch before changing anything else but I still receive the checksum error. I have not tried doing a full flash of any of the cal files afraid I'll brick the PCM if a full flash does not take. Any advice would be appreciated. Thanks.

Can you please post the tune up here?

Sure, I have attached the cal file pre MAF patch (0000) after MAF patch (0002) and the modified cal file (0003). Thanks.

Did any of these tunes previously flash ok?

(0000) was the cal as read from the car when it got it. (0002) started from (0000) and I simply applied the MAF OS patch and performed a full flash successfully. (0003) is (0002) but with modification to the high octane timing table but returns the checksum error when I try to cal flash back to the car. (0002) will also not flash back to the car.

Here you go, try this one instead. Nothing you've done looks like a previous tuner was trying to disguise the tune from GM.

Cheers,
Ross

Great, thanks for your help.

I noticed the file won't open in v7.5 but will in v8. Do I need to flash the cal with v8 and read it back in with v7.5 to edit?

You will probably need to update to this software release...
http://www.efilive.com/latest/softwa...e-apr-13-2015/

Cheers,
Ross

Yep, upgraded and all works fine, the cal you sent flashed without a problem. Thanks again for your help.