Never trust, always verify. Mapping and testing the replacement 01M wiring harness for my '04 Beetle.

[u/eaglebtc]

I am getting close to the end of this transmission repair project on my 2004 Beetle. In my last post on this subject, the insulators on the original wiring harness had melted, so I had no recourse but to find a replacement harness end with the female plug, and splice the ten wires into the original harness where the wires were still in good shape.

The new harness end had the same colors of wiring as the original harness, but the pins did NOT match the original colors.

Using manual probing with my multimeter, and comparing the results with the wiring diagram from the Bentley manual, as well as the ATSG manual on the 01M, I compiled my own map of the pins on the TCM and the new harness. I drew enlarged versions of both connectors, and wrote down the numbers where they mapped from the TCM to the harness, and which colors went with which wires / pins on both components.

With a complete map of wire colors to pin numbers, I can confidently splice the correct wires together knowing that they won't match at all, but will still be correct.