I need to figure out a wiring diagram for some relays

3 way switch on-off-on

Position 1 is the trigger for a relay to close and supply power to lights

Position 2 is open circuit (no power to the circuit)

Position 3 triggers the circuit power relay to close and then switch to another relay that uses the reverse lights as the trigger.

So what I want here is to not have high current sent to the switch, only use it as a trigger switch (it can handle the current but the distance between the switch and relay/fuses makes running heavier wire impractical).

Positions 1 and 3 both energize the power circuit.

However in position 3 in addition to turning on the power it needs disconnect power to the lights except when triggered by the reverse light signal


I want to use no more than 2 relays and I’ve tried every combination my sleep addled brain can conjure and I got nothing.

The tricky bit for sure is telling one relay to close for both events but keeping that relay closed while telling another relay to start looking for trigger signals from the reverse light with the default state open.

I know how to do it with 3 relays or by running all the power through the switch but I’m hoping to avoid that.