tim wellington

i posted this in hp tuner ,no luck yet . i can write or switch tunes 0411 pcm .but will not allow to read starts reading then goes to failed checksum .i am on 4.0 version

G Atsma

It means that the bit count is more or less than original.

tim wellington

meaning? how can i fix it ?

G Atsma

I would call LSX Power Tuning, a sponsor here. They might be able to help you work thru it

tim wellington

thanks i did .they me couple things to try.

PeteS160

If I was to take a guess I'd say it's been flash with an OS from a 99/00 896 pcm. The 896 pcm for all purposes it's identical to a 0411 but there are a few things in the offset of the file structure that can cause issues when swapping OS's between pcm's. Upgrading an 896 pcm to a 411 OS usually works fine and even if it does cause issues they are in a section of the PCM that isn't a big deal. But when you flash a 411 pcm with an OS from the 896 it can get ugly and missing or incorrect check sums are one of the things that can happen. In a lot of cases the only way to correct the issue is to do a complete rewrite back to an OS that belong on the pcm or recalculate the checksums and preform a full flash to rewrite the values correctly.