| Number | X-pin, colour | Description |
|---|---|---|
| X2536 | 13-pin, Black | Plug connector All-round sound combination RTK-4 |
| X2537 | 10-pin, Black | Plug connector All-round sound combination RTK-4 |
| X2538 | 3-pin, Black | Plug connector All-round sound combination RTK-4 |
| X2698 | 3-pin, Black | Plug connector All-round sound combination RTK-4 |
| X3318 | 1-pin, Black | Plug connector All-round sound combination RTK-4 |
| Pin | Type | Description / Signal type | Connection / Measuring notes |
|---|---|---|---|
| 1 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 2 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 3 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 4 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 5 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 6 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 7 | E | Voltage supply terminal 30 | Fuse, officials F01 |
| 8 | A | Signal, terminal 85 | Connector terminal 85 |
| 9 | E | Voltage supply terminal R | Fuse, officials F04 |
| 10 | A | Signal, terminal 84 | Connection, operating unit (BT110) |
| 11 | A | Signal, terminal 72 | Connector, terminal 72 |
| 12 | A | Signal, terminal 84 | Connector, terminal 84 |
| 13 | M | Ground | Ground point |
| Pin | Type | Description / Signal type | Connection / Measuring notes |
|---|---|---|---|
| 1 | Not used | ||
| 2 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 3 | Not used | ||
| 4 | Not used | ||
| 5 | A | Signal, terminal 49 | Connection, operating unit (BT110) |
| 6 | A | Signal, terminal 49 | Connection, operating unit (BT110) |
| 7 | Not used | ||
| 8 | Not used | ||
| 9 | Not used | ||
| 10 | A | Signal, terminal 49 | Connection, operating unit (BT110) |
| Pin | Type | Description / Signal type | Connection / Measuring notes |
|---|---|---|---|
| 1 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 2 | A | Signal, operating unit | Connection, operating unit (BT110) |
| 3 | M | Shield | Radio shield |
| Pin | Type | Description / Signal type | Connection / Measuring notes |
|---|---|---|---|
| 1 | A | Signal, microphone | Connection, operating unit (BT110) |
| 2 | M | Shield | Radio shield |
| 3 | A | Signal, microphone | Connection, operating unit (BT110) |
| Pin | Type | Description / Signal type | Connection / Measuring notes |
|---|---|---|---|
| 1 | M | Ground | Ground point |