In the absence of the standardised 16-pin EOBD socket, you will have to research your particular vehicle’s requirements. Sometimes, manufacturer-specific tools that you need are now obsolete. However, in some cases, aftermarket software may have been developed, through which you can access live data, such as the packages for Rover Group MEMS systems (see CM, May 2016). Otherwise, enthusiasts of a specific model of car may be able to help.
Some pre-2001 vehicles had their own non-standardised ‘blink codes’, which relied on a flashing LED that had to be translated by a technician. Even so, some of them were fairly sophisticated and you may be able to activate certain components to check that they operate. Should you need live data on such PRE-EOBD vehicles, a multimeter and/or oscilloscope are the preferred measuring tools.