16/05/2026
Spark Auto electrics
ON BODY DIAGNOSTIC PIN OUT
Modern DAF trucks use a heavy-duty, 24V variant of the standard 16-pin OBD2 (SAE J1962) shape port, heavily utilizing the J1939 CAN bus network protocols rather than the standard OBD2 systems seen in passenger vehicles.
Note that because DAF operates on a 24V electrical system, standard 12V consumer OBD2 scanners will fry if plugged directly into a DAF port without a step-down converter or a dedicated heavy-duty scanner like the DAF VCI 560.
DAF 16-Pin OBD2 Pinout Diagram
The standard pins utilized in DAF Euro 4, Euro 5, and Euro 6 models (such as the DAF LF, CF, and XF series) follow this layout:
Pin Number Signal Name / Function Protocol / Description
Pin 1 +24V Ignition Power Switched power line from the ignition circuit.
Pin 2 CAN-H (J1939 Engine CAN) Vehicle CAN High bus communication.
Pin 3 CAN-L (J1939 Engine CAN) Vehicle CAN Low bus communication.
Pin 4 Chassis Ground Connected directly to the vehicle chassis frame.
Pin 5 Signal Ground Reference ground for data communication lines.
Pin 6 CAN High (ISO 15765-4) Diagnostic CAN High network link.
Pin 7 K-Line (ISO 9141-2 / Keyword 2000) Legacy diagnostic line for older ECUs and system initialization.
Pin 14 CAN Low (ISO 15765-4) Diagnostic CAN Low network link.
Pin 15 L-Line (ISO 9141-2) Secondary diagnostic data line (optional depending on module).
Pin 16 Battery Power (+24V) Permanent live battery feed (Fused).
Note: Pins 8, 9, 10, 11, 12, and 13 are mostly manufacturer-specific lines often used for dedicated brand sub-networks or are unassigned depending on the cab configuration.
Important Diagnostics Precautions
Check the Voltage: DAF pin 16 supplies 24V battery power, unlike the 12V standard on consumer vehicles. Connecting a normal car scan tool will instantly destroy your equipment. Ensure your equipment explicitly lists 24V commercial vehicle support.
Adapter Matching: If you are connecting an older heavy-duty system or generic tracking device using a 9-pin Deutsch J1939 adapter, make sure the adapter maps Pin 2 (CAN-H) and Pin 3 (CAN-L) correctly to standard pins 6 and 14 on your end device.
Data Link Safety: Avoid probing pins 2, 3, 6, or 14 using a basic test light. These are complex multiplexed data buses. Shorting them out can drop critical vehicle controllers offline, resulting in cluster faults or engine cranks with no-start scenarios.