The connector that's mounted in the car looks like this:

All ISO compatible cars with have pins in all of these locations with, maybe, the exception of the L Line. The L Line is used to wake up the ECU but this can be done via the main data line (K Line) on most newer ECUs.
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Here is OBD-II ISO interface:

The interface is fully ISO compliant, interfaces with both the K and L lines, opto-isolated from the vehicle's data-stream and comes complete with status LEDs. The flow control lines are also connected which makes the interface more universal and compatible with a wider range of software.
The version 2 board has a selectable link (LK1) which can be used in two configurations:
The version 2 interface also has the facility to fit fuses on both the K and L lines.
This interface will also interface with most Audi and Volkswagens including those with a two-pin connector (not-included).