OK thanks for the really quick answer.
I'm trying to trouble shoot a problem on the binnacle lights.
I removed the binnacle - had my speedo rebuilt and whilst at it got LED bulbs - except the incandescent one for the alternator.
I tested each LED bulb and marked each bulb so I knew which side of the bulb was positive and negative.
Next I used a simple battery powered continuity tester on the binnacle Flexi PCB and marked what (I thought) were grounds
Now, the only binnacle led bulbs that work are the ones that come on with the side lights (Dimmer is therefore turned up full ... because of the knock on LED dimmer problem).
The incandescent bulb no longer works neither does the oil light ...... thats why I was wondering if the unplugged multiplug I asked about ... was causing a continuity problem?
Edit - Thinking out loud - I should check the fuse box !!! It's late here ..... I'll check it tomorrow ... this car is fighting me grrrr!