I’m going to explain quickly the process of modifying the wiring on a VW T5 to allow the use of T5.1 (facelift) headlights.
The pins can be easily swapped using a Laser 3932 Terminal Tool (or similar) <see the video below>
Left / Passenger Side Wiring
| Original Pin (T5) | New Pin (T5.1) | Description |
| PIN1 | PIN1 | Purple / Yellow; Headlamp Leveler |
| PIN2 | PIN7 | Empty |
| PIN3 | PIN3 | Thin Brown; Ground |
| PIN4 | PIN5 | Thick Brown; Ground |
| PIN5 | PIN2 | Red / Blue; Headlamp Leveler |
| PIN6 | PIN9 | Black / White; Indicator |
| PIN7 | PIN6 | Yellow Black; Dipped Beam |
| PIN8 | PIN5 | Thin/Medium Brown; Ground |
| PIN9 | PIN8 | White / Black; Main Beam |
| PIN10 | PIN10 | Purple / Black; Sidelight |
Right / Drivers Side Wiring
| Original Pin (T5) | New Pin (T5.1) | Description |
| PIN1 | PIN1 | Yellow / Grey; Headlamp Leveler |
| PIN2 | PIN7 | Empty; |
| PIN3 | PIN3 | Thin Brown; Ground |
| PIN4 | PIN5 | Thick Brown; Ground |
| PIN5 | PIN2 | Red / Blue; Headlamp Leveler |
| PIN6 | PIN9 | Black / Green; Indicator |
| PIN7 | PIN6 | Yellow; Dipped Beam |
| PIN8 | PIN5 | Thin/Medium Brown; Ground |
| PIN9 | PIN8 | White; Main Beam |
| PIN10 | PIN10 | Grey / Red; Sidelight |