Only the X 12 XE-specific modifications regarding X 10 XE terminal assignment are listed below. The remaining X 12 XE engine control unit wiring harness plug terminal assignment is essentially identical to that of the X 10 XE (see "New Technical Features MY '97 1/2", section 5.8).
| A6 | Injection valve 1, Y7-1 |
|---|---|
| A7 | Injection valve 4, Y7-4 |
| A10 | Ignition module L2 (ignitor 2) |
| A16 | Injection valve 3, Y7-3 |
| A17 | Injection valve 2, Y7-2 |
| A19 | Ignition module L2 (ignitor 3) |
| A28 | Ignition module L2 (ignitor 4) |
| A38 | Ignition module L2 (ignitor 1) |