high beam flash arm/disarm

I am using a relay to make my current alarm installation flash my high beams when I Arm/Disarm my alarm. Here is my diagram: Ok here is the problem I am having. It works fine when i disarm/arm, but when I turn my headlights on the high beams come on with the headlights. Then when I pull the high beam switch the high beams come on brighter. So I don't understand what my problem is.

Ya when the relay is unhooked everything is fine. I've tried wiring to the + on the high beams with the same outcome.

That's strange. When that relay is not energized, it is not (should not I guess I should say) doing anything. What brand is the relay? Have you tried a different relay?

use negative triggers for the headlights. wire relay like so.

85 - alarm positive output from alarm

86 - ground87 - high current ground 87a - highbeam neg wire (switch side)30 - highbeam neg wire (bulb side)

doing it like so will prevent backfeed onto other lights.

OK thanks guys will try tomorrow and let you know how it goes and what do you mean by high current ground? One that goes to the battery as opposed to the body?

same thing as a good clean spot on the chassis.

tedmond, assuming the car is a standard negative ground vehicle, how does switching the ground path for the headlights light them up? The problem is that your output from your alarm parking light output is connected directly to your relay coil since you don't have any isolation, so if you turn on your parking lights, the relay will turn on and close the contacts. Best way to go about it is to add a relay driven by your alarm's parking light output, and use that to power your parking lights, and then use a second relay driven off the same line. That way turning on your parking lights won't energize this added relay.

The lights draw a relatively large current, so it would require large diodes to handle it. Diodes in this case will waste power (approximate watts = current draw X 0.7V) so they'll get hot if the lights are on for any extended time. High beams of 110W will draw over 9A, so the diode will have will have to dissipate over 6W. Doesn't sound like much, but give it a try and see how hot that is when it's not going out as light. If the alarm output is only on for very short periods you might get away with it. In any case, high current diodes would be necessary, the run of the mill 1N4001 1A diodes won't cut it.