Relays and Wiring
Standard relay pins
Most relays are numbered according to the D.I.N. standard. When a circuit is completed between pins 85 and 86, the relay is tripped to complete the circuit across pins 30 and 87.

30 -12 V+ Power (usually taken from low or high beam fuse)
85 -Power from dash switch
86 -Ground
87 -To lights (or other appliance).


January, 1999

Dave James, Turbo! subscriber, posted the following diagram and text:

This diagram shows how to wire up relays for fog and driving lights with some relay grounding tricks to kill the fogs when the high beams are on and kill the driving lights when the lo beams are on.  It will give you the basic way to wire a relay to shed the load.

If you are generating 100 watts on a circuit designed for less than 50 you may need to beef up the wires that carry the load in order to lower connector temperatures.


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