| Number | X-pin, colour | Description | 
|---|---|---|
| X01021 | 9 -pin, Black | Plug connector Relay, compressor pump control | 
| Pin | Type | Description / Signal type | Connection / Measuring notes | 
|---|---|---|---|
| 1 | Not used | ||
| 2 | E | Terminal 30 | Fuse F51 | 
| 3 | Not used | ||
| 4 | E | Relay activation | Air suspension control unit | 
| 5 | Not used | ||
| 6 | A | Terminal 87 | Compressor pump | 
| 7 | Not used | ||
| 8 | M | Ground | Ground connector | 
| 9 | Not used | ||