ECUHELP KT200II is confirmed to read and write Audi A6 4G EDC17CP54 Bench Mode.

Look at the ECU of Audi A6 4G EDC17CP54:
KT200II Read Write Audi A6 4G EDC17CP54 Bench Mode

Look at this image on how to connect KT200II to the EDC17CP54 on Bench.
KT200II Read Write Audi A6 4G EDC17CP54 Bench Mode

Look at the images on reading 100% OK.
KT200II Read Write Audi A6 4G EDC17CP54 Bench Mode KT200II Read Write Audi A6 4G EDC17CP54 Bench Mode

KT200II wiring diagram of BOSCH EDC17 CP54 [ 1793 ] – Volkswagen, Audi, Seat, Skoda [Diesel] :
Connect the multifunction cable as follows:
KT200II Read Write Audi A6 4G EDC17CP54 Bench Mode

KT200II to read and write use the following driver:
→ BENCH TRICORE
→ VAG
→ TC1793 – VAG
→ EDC17 CP54