Location of Link ECU knock sensor?

The knock sensor lead is loose in the engine compartment, can’t see where it plugs in?

Unfortunately Simon, who looked after the car for 14 years, died and need to know where its located. Should be obvious but simply can’t work it out

TIA

you don’t say which end - so, one end plugs into the box which should be mounted on the inside of the n/s wings

and the other end plugs into the knock sensor mounted on the drivers side engine mount - the manual says to remove one of the bolts and 

replace it with the knock sensor

 

HTH