pcmhacking.net

Hi guys im trying to edit a vt supercharged v6 file it tune fine but as soon as i alter the tune it brings up code 51 memcal error, everything else works just the cel stays on with this code im using Tuner Pro 5 a CNPM base file with a A5F xdf what am i doing wrong ?

Checksum Change the byte at 0x2008 to AA instead of A5. TP cannot handle the checksum update so need to tell the PCM to ignore it.

So you leave 2007 as it is and change 2008 to aa done in the hex editor directly is that right?
I changed checksum from FF31 to FFAA but still code 51?

I did have 1 like this not so long ago, but was when I was starting & forgot to blank check the memcal before writing onto it!

It did everything fine but had memcal error I'd try that, I have been using the same pcm's in the car's I've done & haven't had to do the AA Check sum thing!

For the checksum bypass your not changing the checksum your changing the program ID byte (originally A5 as VT S/C are all program id $A5 variants) as thats whats tested at start up to decide if its going to checksum the whole bin or not.

OK, I've updated the VT $A5 xdf for Variants F&K to fix the checksum.
Latest can be downloaded from here :
https://pcmhacking.net/forums/view ... ?f=7&t=270

You can either change the "VT Program ID Code $A5" to $AA, or leave it as $A5 as now the checksum should work.
Let me know how you go.

Good Luck,
yoda69

Thanks for the quick reply thats all it was changed the program id to aa and no more light thanks again will try the software out this week and see it it works