| J... | Engine control units |
| J285 | Control unit with display in dash panel insert |
| J533 | Data bus diagnostic interface |
| T16 | 16-pin connector, near handbrake lever, self-diagnosis connection |
| T32a | 32-pin connector, blue, on dash panel insert |
| T32b | 32-pin connector, green, on dash panel insert |
| 30 | Earth point -1-, next to relay plate |
| 81 | Earth connection -1-, in dash panel wiring harness |
| A76 | Connection (diagnosis wire K), in dash panel wiring harness |
| A146 | Connection (convenience CAN bus, high), in dash panel wiring harness |
| A147 | Connection (convenience CAN bus, low), in dash panel wiring harness |
| * | Only models with tachograph |
| J255 | Climatronic control unit |
| J393 | Convenience system central control unit |
| J453 | Multi-function steering wheel control unit |
| R | Radio |
| T10a | 10-pin connector, brown |
| T16d | 16-pin connector, black, on radio |
| T20 | 20-pin connector, red, on climatronic control unit |
| T18m | 18-pin connector, black, on multi-function steering wheel control unit |
| T23 | 23-pin connector, black, on convenience system central control unit |
| A146 | Connection (convenience CAN bus, high), in dash panel wiring harness |
| A147 | Connection (convenience CAN bus, low), in dash panel wiring harness |
| W64 | Connection (convenience CAN bus, high), in floor wiring harness |
| W65 | Connection (convenience CAN bus, low), in floor wiring harness |
| * | Only models with 'Delta' radio |
