momentary output after ign off

Hello all ... I need a relay to activate a solenoid after turning off the ignition. I would like the relay to not use any power after the pulse. I was thinking of using the alarm's locking signal for this but would prefer something that worked even if the alarm wasn't used. I also thought of using the doors lock button but I would need a way of ensuring that it only worked when the ignition was off because my truck locks automatically when I go over 20mph and i dont want the solenoid to work while driving..only parked. But how do I do that? I would prefer something that worked automatically when i turned of the ignition and would remain passive. Any Ideas?    I could really use some help with this....Thanks

please explain in more detail what you are trying to accomplish.

yuk

quiet rural missouri, near KC.

If your system moves you physically and not emotionally, you have wasted your money.

I need to send a momentary pulse to a solenoid after i turn off the ignition and not have the relay draw current after the momentary pulse.

Go to the relay section on this site look for constant neg input and momentary output, use your ignition wire to terminal 85 via resistor and capacitor.

Thank you for your response I looked under the link "Relay Diagrams - Quick Reference" (Last Updated: 5/7/2011) there was 4 diagrams for constant to momentary and 2 were neg input ,but all showed a neg at pin 85 where you said i should connect my ignition. Then i remembered this post i came across--https://www.the12volt.com/installbay/forum_posts.asp?tid=60614&tpn=1&PN=1 it looks like the neg to neg diagram in the quick ref except the coil polarity and capacitor are reversed.   looks like it draws current momentarily when ign is first turned on and releases the pulse with ign off and draws no further current..   Is this correct? Thanks again for your help

The one I was thinking of showed a neg switch at 85, this is the ignition which will show NEG when turned off. Please try to understand that a POS ignition wire shows NEG when you turn it off. Test if you don't believe me but you will be wrong. Gives you a POS output at 30. 85 is conventionally (ISO wiring pin convention) the NEG of the coil, 86 the POS.

See if you understand it better now. constant_to_pulse.bmp

thank's for the diagram. i did not know that the pos ign wire showed neg in the off position...i thought it became an open circuit. Does the relay draw a small amount of current throught the 10k resistor while the ign is off?

How can it on a NEG ground vehicle, also don't forget the diode across the relay, that acts as a current block.

I'm trying to fully understand this... What stops 1ma (12/10k) of current from going from the constant 12v source through the coil and resistor to the now negative ign wire ?