the 968 DME plug's pin 27 (black wire) needs "key on" 12v power, that is the key switch term 15 (black wire)

in some models the pin 7 (black/yellow) in the foot well may connect to 968 DME plug's pin 27 electrically (it does in early 968's)...just be sure it is coming from key switch term 15 (black wire)...else you may drain the battery

...the original 968 gets the 12 volts to DME plug's pin 27 through the 968's alarm circuit.