Meter Signal Delay

[turtle64b]

So I have ProSport aftermarket meters installed. These meters will change color from blue to red when the lights are turned on. When the headlights are in auto, if the conditions are met for the lights to be on, then the "switch" signal (signal to change the meters from blue to red) becomes the base voltage and the meter color stays blue until you turn the car off and back on.

My question is: Has anyone fashioned a delay circuit to prevent the "on" voltage from reaching the meter right away and allowing the meter's color switch function to work properly.

There was a writeup on the Subaru forum utilizing a 555 chip, a 100k ohm resistor and a small capacitor wired up to delay the signal that determines the color of the meter. I cannot seem to find that article, but as soon as I do, I will link it here.

Thanks!!

[SouthArk370Z]

Do a web search for "555 delay latch". The 555 is one of the most popular chips of all time.

[turtle64b]

This is the thread to it:

https://forums.nasioc.com/forums/sho....php?t=1886784

Dude made the circuit and it was about the size of a penny.

There is an "all about circuits" forum that I might use to build the circuit.

[turtle64b]

I think I found it, thank you!

https://circuitdigest.com/electronic...ircuit-diagram

[SouthArk370Z]

Originally Posted by turtle64b

I think I found it, thank you!

https://circuitdigest.com/electronic...ircuit-diagram

This circuit will work but you'll have to make some adjustments for 12V system (eg, 7909 voltage regulator instead of 9V battery). There should be a simpler way to do it (eg, without variable time delay) but the circuit will do the job. There's LOTS of info and circuits for 555s out there; you should be able to find a circuit that requires a lot fewer parts.

[Tractionless]

STrange my Prosport model turns on white and stays white until I use the button to change to amber. Not doing anything on its own.

[Optimiser]

Originally Posted by Tractionless

STrange my Prosport model turns on white and stays white until I use the button to change to amber. Not doing anything on its own.

[turtle64b]

Originally Posted by Tractionless

STrange my Prosport model turns on white and stays white until I use the button to change to amber. Not doing anything on its own.

I'm running the Prosport Evo series, which doesn't have a button to switch colors. It has a signal wire driven from the ILLUM signal to the radio dependent on whether the lights were on or not.

I could wire in a switch in lieu of a delay circuit, but I would rather have it done automatically as designed.

The circuit built in the link to the Subi forum is the size of a penny and uses 4 total components on a small circuit board. Basically a 555 chip, two capacitors and a resistor.

Thank you guys for the inputs!