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Hi there all, still working on things, promise some photos this week.

Have installed a H4 conversion kit, which included two H3 100 watt highs, which I have connected through a relay and switch.

To trigger the relay need a postive feed from the dip switch, so tapped into the white wire on number 50 plug connector.

All should work, but the white wire carries power when dip switch is undipped, loses power when highs are selected.

So a bit stumped. Could connect up to the high wire up at the H4 lights to trip the relay, but wanted to keep things simple under the dash.

Any thoughts would be welcome

Chris

Easiest way would be to use the same wiring but use a NC (normally closed) relay. When the relay is triggered it disconnects the circuit (so the high beams wont work), when the relay circuit is inactive (no power) it closes the circuit (and the high beams would come on).

Should match you dip/undipped combination. Can get them in a bosch 5 pin relay, you'll find them with pin 87 and 87a. 87 is NO (normally open) operation, 87a should be NC (normally closed) and the one you want. They are called SPDT relays and look like this;

thanks for the response - appreciate it - needed one of these when I installed some DRLs into my old e36.

Am fiddling around the dash over the weekend, sorting out some other issues around the aircon. I think I will take out the instrument binnacle and tap into the wire that provides power to the blue (high beam) bulb.

Regards - you have an awesome looking car - Chris