incorrect checksum symptoms??

[gitto]

hello guys, i'm new here, i have problem with tuned file, it's paid one, bought from russian tuner and my friend edited that bin with xdf that is uploaded here in download section (it has automatic checksum correction), he increased rev limit and retarded ignition slightly(was bit much for low octane fuel), other maps looks OK with my limited knowledge, he burned chip with willem programmer and when i installed it in the ECU, the car starts very hardly and stalls imediatelly, is that wrong checksum? the car fires up very hard,backfiring and shuts off within miliseconds. with stock chip everything is fine..

[olafu]

Car? ECU number? BIN number and XDF what was used to edit it.
As example 413 ecu with 623 bin only sets trouble code if checksum is wrong.
Most likely wrong XDF was used. ECU goes reset loop if map header data is broken. Wrong offset in XDF can cause this.

[gitto]

e34 525i with 405 ecu 951 bin and xdf is for 950 bin 403 ecu (i was told they were same )
i've checked checksum manually and it's correct, tunerpro plugin did a job

[olafu]

And everything looked logical on tunerpro, when your friend edited it?

[gitto]

yes, the car was running well with this tune before editing. but sometimes it was knocking (engine has 11:1 CR) that was the reason of retarding ignition in PT and WOT maps. today we've copied idle, pt, wot ignition and fuel maps in 950 bin with tunerpro and car starts well, is there any chance that bin structure is modified by tuner and tunerpro xdf messes with it?

[Evil]

I've seen this "1utomatic checksum correction" in some xdf but it doesnt work.
Anyway like olafu said, a bad checksum only causes a CEL, I personnally never change checksum on my tunes, I have just deactivate checksum dtc.
Your xdf was probably wrong