Adapter cables for trucks, trailers and agricultural machinery
In the commercial vehicle sector, the flat 16-pin OBD2 socket is by no means found everywhere. Older trucks, trailers and semi-trailers as well as many agricultural and construction machines have round manufacturer-specific connectors with 6, 7, 9, 16 or 37 contacts. To connect your diagnostic tool nonetheless, you need the right adapter cable. This guide shows which cable goes where.
Overview: commercial vehicle and machinery connectors
| Vehicle / system | Connector on the vehicle | Suitable adapter cable |
|---|---|---|
| MAN commercial vehicles | 37-pin, round | MAN 37-pin to OBD2 |
| Older Scania commercial vehicles | 16-pin, round | Scania 16-pin to OBD2 |
| Commercial vehicles with 9-pin or 6-pin round connector | 9-pin or 6-pin | Truck 9+6-pin to OBD2 |
| Trailers, semi-trailers, braking systems (Wabco) | 7-pin | Wabco 7-pin to OBD2 |
| CASE, CASE IH, New Holland, Steyr, Flexi-Coil, Kobelco, Müller | 9-pin | CNH 9-pin to 16-pin OBD2 |
Important: An adapter cable is not a diagnostic tool. It only provides the mechanical and electrical connection between the vehicle and the diagnostic tool. Which control units and functions you can reach always depends on the diagnostic tool used, its software and the manufacturer, model and model year of the vehicle.
MAN: the 37-pin round connector
Many MAN commercial vehicles have a manufacturer-specific round connector with 37 contacts instead of the OBD2 socket. The adapter cable connects it to your 16-pin OBD2 diagnostic tool – so your existing workshop equipment and interfaces remain usable.
Scania: 16 contacts, but round
Older Scania vehicles have a round 16-pin connector. Although it has as many contacts as the OBD2 socket, its design is completely different – a normal OBD2 plug does not fit. The adapter cable ensures a firm, wobble-free fit.
Truck 9+6-pin: one cable for two connectors
Two round connectors are common in the commercial vehicle sector: with 9 and with 6 contacts. Which one is fitted varies from vehicle to vehicle. The dual connector covers both variants – you do not need to carry two separate cables.
Wabco 7-pin: trailers and braking systems
Trailers, semi-trailers and the braking systems of commercial vehicles usually have their own 7-pin diagnostic connector. With the Wabco adapter you can use your existing diagnostic tool here too.
CNH: tractors, combine harvesters and construction machinery
Many agricultural and construction machines from CASE, CASE IH, New Holland, Steyr, Flexi-Coil, Kobelco and Müller have a 9-pin diagnostic interface. The shielded CNH adapter cable connects it to the 16-pin OBD2 interface of modern diagnostic tools. Please check the diagnostic socket of your machine before buying – compatibility depends on the model and interface.
The right diagnostic tool
Which systems you can reach on a commercial vehicle is determined by the diagnostic tool. Our comparisons help you choose: The best truck diagnostic tools, Diagnostic tools for coaches and Diagnostic tools for Case, New Holland and Steyr.
Conclusion
In the commercial vehicle and agricultural machinery sector, the connector is what counts: MAN 37-pin, round Scania, 9+6-pin dual connector, Wabco 7-pin for trailers or CNH 9-pin for tractors and construction machinery. With the right cable, your existing diagnostic tool remains ready for use everywhere. You will find all cables in the truck adapter cables category. You can buy on invoice via Klarna or PayPal. Advice on 0711-3654 4645.