Friends sorry to ask but I need some help. I have been trying to do a simple tune with cat delete for an 2007 Audi Q7 4.2V8 FSI MED9.1.1 4L910560B 0070 without suces.

Does not matter how simple I left the difference between original and modified file (for example CDKAT set to zero only), ECU becomes blocked after a sucessful reflash process. Battery charger was used. Kessv2 was used. Kess file is 2544Kb. Ktag one is 2560Kb. File was checksummed by WinOLS and KSuite too. These ECU does not accept any file I write to it.

I have done the same Audi Q7 before with same process 2544Kb files form Kess without any problem. Is there any tuning protection in the SW version do you know? The only weird detail is the ECU appears "not registered" in VCDS CAN Gateway list. It also is unchecked in the CAN Gateway list but that Q7 is working normaly.

Some advice will be awesome. Thanks.