D Group 37 Wiring diagram FL Example of wiring diagram Wiring numbers Wire equipotential: Equipotential is a wire propriety which characterize a signal flowing a wire (same signal = same equipotential). Several wires could have the same equipotential. Example of wiring numbers. T3018844 Starting switch Switch logic diagram. 5 The first digit of the number Family 1 Ground and negative supply 2 Positive supply 3 Signal 4 Comfort accessories 5 Security accessories 6 Lighting 7 Instrumentation 8 Body builder 9 Free 0 Electronic/Data link Terminal Key in position Key inserted — “0” — “I” — “II” — “III” Key inserted (1) Off Accessories (5) +15/DR (3) 50 (2)