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Momentary circuit help Answered

Hi, I need some help with making a circuit. I'm new here and dont have much experience with electronic components. I need a 12v circuit that whenever it receives power it waits 3 seconds then grounds the load in the circuit for 1 second. Then stays off until power is removed. It must reset every time it gets power. Any help is greatly appreciated! Thank you!

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iceng

8 days ago

A NE555 8pin IC (integrated circuit) timer as a one_shot driving a transistor mosfet should easily pull the ECM to ground.
The question now remains what signal indicates the engine has successfully started or is the act of turning the ignition key mean vehicle start ?

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iceng

14 days ago

What is the load impedance 12V and ohms or current ?..
Could you mean turns off the load after 3s ?..
Could you mean disconnect the load from 12V and
then ground it (like halting a small DC motor) ???

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ortegadrian222iceng

Reply 13 days ago

Sorry for my poor description. The purpose of this circuit is to ground a switch on a car ecm once per key cycle. So it should wait for the vehicle to start, then ground the ecm switch for 1 second, then shut off for the rest of the key cycle. I hope my crude drawing can help explain.

Screenshot_20190702-175759_Samsung Notes.jpg