It will then attempt to "Check for Password." This is where the GPT cable does its work.
Ensure you are using KSuite 2.23 or 2.25. Versions older than 7.020 firmware often lack the GPT algorithms for newer EDC17 units. How to read Mercedes EDC17CP57 with Ktag 7.020 GPT cable
Ensure the GPT 1 and GPT 2 wires are not swapped. These are polarity sensitive. It will then attempt to "Check for Password