efi help solve this one.

[dmax]

i took my stock van tune and loaded the alternate lbz tune on efilive, i then used the edit pull down menu and copyed the entire segment of the "lbz engine operation" the checksum value changed after saving the tune and to confirm that i infact copyed over the "engine operation" section of the lbz time i reopened up this tune i just saved. sure enough the id changed and the checksum is now the same as the lbz tune values all others are the same as my stock van tune. also the calibration file .cal changed to the lbz # of 12606128 from 12606129 that of the van tune. now, when i loaded the tune into my truck the key is completely dead, meaning it will not even try to start. the engine operation of the tune was the only thing changed. can anybody resolve this and why is it doing it? btw passlock is disabled. i figured since the engines of the van and lbz are identical this would be just a program change, but something is shutting down bigtime, also no dtc to speak off.

[Cougar281]

Sounds like something in the LBZ Engine cal isn't compatable with something on the Van. I'm not sure what else is different, but obviously the TCM is different. I'm assuming the OS is the same (since you did a copy segment). Might be better off comparing the two and then copying the different tables from the LBZ tune to the Van tune. My only concern though could be thr transmission. Can it handle the LBZ's tourqe? Just my thoughts...

[dmax]

same os for both, yes the tcm is different, and yes my tranny will hold, i have been running a modified tune all summer and it is night and day compared to the van tune. as for comparing each tune, as i said before everything is the same for both but there are things which cannot be seen with the efi software, the ecm is not completely hacked imo. i have seen this with gas engine efi like tunercat.

[GMPX]

It is probably a platform specific setting not allowing it to crank, eg, it is looking for a specific CAN message or some input state before it is allowed to crank.
One of the issues with the Van tune is the table sizes vary between it and the regular trucks on the same OS, this makes table copying a problem, it's also the reason why we force it to use a different .cal file because the two are not the same in reality.

Cheers,
Ross

[dmax]

can this be corrected? without changing back to the van engine operation checksum? can a tech2 candi module fix this?