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I get frustrated with constantly having to turn my foglights on after I shut the power off. I'm looking for a simple relay circuit with memory so it remembers the last state it was in. Any help much appreciated. Thanks

You know that a NMOS and a PMOS keep their "state" ON or OFF for some time. The typical example is to turn ON a NMOS simply by touching its gate with your hand, and even if you remove your hand, the transistor stays ON ... for some time. Adding a capacitor in series with the gate could increase that "memory" time from few minutes to many months. It is generally not done because that would make the switching time ON to OFF to ON relatively terribly slow (3 times C times the resistance seen by the capacitor), which is the reverse of what we generally want when dealing with Gigahertz. But here, if it takes few milliseconds to respond, from ON to OFF or OFF to ON, who cares?

I don't know if you circuit is using a NMOS (or PMOS) to start with, though, so I can't tell if it is practical or not, to use a capacitor (with low leakage) in your case.

I'm trying to bypass the foglight switch on my car. It's a momentary contact on the column. When I activate it, the fog lights come on, but when I turn the car off the relay resets to the off state. I'm trying to activate the switch once and have it keep the on state even when I turn the car off.

Many ways to do.. This is worth a try if you need to keep the Push Button... You'll need another PB that is normally closed to be the OFF button.

Thanks. I'll give it a try

Would this work? DPST 1NO 1NC 8Amp Latching Relay Module (DC 12V) https://a.co/d/bW3MGUn

From the mixed results in comments that it received, at best, it depends on the kind of load it drives.

The connection location needs to be precise. I quite like it when you describe the detailed drawing to follow and update the design accordingly.

https://a.co/d/bW3MGUn Geometry Dash Lite

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The connection point must be exact. I appreciate it when you explain the full drawing so that I can follow it and adjust the design as necessary. https://a.co/d/bW3MGUn Block Blast

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