Momentary Relays

Hi all,

I have a question about the following momentary relay circuit.

https://www.the12volt.com/relays/page5.asp#ctm

If the switched 12v stays switched on will the R/C circuit continue to bleed the circuit and keep the relay open until the switched 12v is removed?

I have a central locking system in my daughters car and when you lock the car one wire goes to 12v and stays there until the car is unlocked. What I would like to do is use this circuit to flash the turn signals to show the car is locked. What concerns me is draining the battery while the car is locked.

Then when the car is unlocked and a second wire goes to 12v I would use a second relay to switch on the interior light until she starts the car (this would mean a latched circuit I guess that is turned off by starting the car).

Thanks

RogerG

Once the capacitor is charged, the relay coil will deenergize. If you use a 10k bleed resistor as in the diagram, current draw will be negligible (1-2 ma), and you won't have to worry about it.

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My ex once told me I have a perfect face for radio.

Thank you.

Find a lock motor wire, this will stay either on ground (99% of vehicles) or be open circuit.
It should show 12 V+ for between 0.4 and 0.8 seconds.
Run a wire from there (either door loom) to relay 86, 85 to ground then 15 amp fused constant to 87, out from 30 via two wires, one for each side BUT a 3 amp diode inline, 1N5404, bands away from relay.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Thank you, I will double check but the wire goes to 12v and stays there.

Then I don't think you've found a motor wire.
How's about make model and year, help us to help you.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

It's an after market system, pretty common. Blue and green wires to slave actuators, brown, white, blue and green to the master. The brown goes high when the doors are locked and the white goes high when they are unlocked.

Green should be motor lock wire.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.