OBD-II diagnostic connector

OBD-II diagnostic connector


The OBD-II system specifies a standardized hardware interface—the female 16-pin (2x8) J1962 connector. Unlike the OBD-I connector, which could be under the hood of the vehicle, the OBD-II connector usually locates under the dashboard on the driver’s side. This is because the specification has required the port to be within 2 feet (0.61 m) of the steering wheel for convenience concern. The only exemption is applied for by the manufacturer, but it is still somewhere within reach of the driver.
 
SAE J1962 defines the pinout of the connector as:
 
1 Manufacturer discretion -
GM: J2411 GMLAN/SWC/Single-Wire CAN
VW/Audi: Switched +12 to tell a scan tool whether the ignition is on.
Ford: Infotainment CAN High
9 Manufacturer discretion -
GM: 8192 baud ALDL where fitted.
2 Bus Positive Line of SAE J1850PWM and VPW 10 Bus Negative Line of SAE J1850 PWM only (not SAE J1850 VPW)
3 Manufacturer discretion -
Ford: DCL(+) Argentina, Brazil (pre OBD-II) 1997-2000, USA, Europe, etc.
Ford: Medium Speed CAN-High
Chrysler: CCD Bus(+)
11 Manufacturer Discretion -
Ford: DCL(-) Argentina, Brazil (pre OBD-II) 1997-2000, USA, Europe, etc.
Ford: Medium Speed CAN-Low
Chrysler: CCD Bus(-)
4 Chassis ground 12 Manufacturer discretion -
5 Signal ground 13 Manufacturer discretion -
Ford: FEPS - Programming PCM voltage
6 CAN-High (ISO 15765-4 and SAE J2284) 14 CAN-Low (ISO 15765-4 and SAE J2284)
7 K-Line of ISO 9141-2 and ISO 14230-4 15 L-Line of ISO 9141-2 and ISO 14230-4
8 Manufacturer discretion -
BMW: Second K-Line for non OBD-II (Body/Chassis/Infotainment) systems.
Ford: Infotainment CAN-Low
16 Battery voltage
 
The assignment of unspecified pins is the vehicle manufacturer's discretion.