very, very 12v split second delay

[gtr33m]

This topic has been covered here before, but in this case I'm looking for a very simple, ie one or two component solution that is not mission critical if it doesn't work every time.

Essentially I have a small relay that triggers a switch on a reversing camera setup when the car is put into reverse. This works fine, however I don't want it to trigger the relay when car is taken from park to drive. There is a split second where the shift lever passes through reverse that I don't want to activate the relay.

I am a complete novice, but figured that some sort of resistor capacitor combination would give me the split second delay I need, especially since I am only driving a relay and nothing else.

I can purchase a time delay relay but I'd rather use the relay I already have and have something that fits inside the existing box.

Thanks,

Mark

 

[alec_t]

What coil current does your relay draw?
Is the switch to the relay coil in the +ve lead or in the ground (-ve) lead?

 

[gtr33m]

The relay is a 221D012 dpdt PCB type. Information I can find says 2 amp, but I'm not sure if that's the draw or the Max current it can handle. 2 amps sounds very high for such a small relay.

If I understand your to the question properly, the switch to the relay is to the positive, as the power to the relay coil comes from the reverse light +, whereas the relay itself is connecting the - to a point on a board which switches the input on the screen.

Hope this makes sense. I know the terminology is all wrong.

Mark

 

[ronv]

Delay

Something like this should work. Almost any P Channel FET will work, but since it is in a car a 60 volt or higher might be advised.

 

[gtr33m]

Thanks so much.

I think I have the diodes and resistors in my junk drawer already. Could I change the cap to a 22uf? I ask because I already have a bunch of these left over from another project.

Mark

 

[ronv]

Could I change the cap to a 22uf? I ask because I already have a bunch of these left over from another project.

Sure, It will just make the delay a little longer.