I'm trying to wire in 2 LED with one switch each. I can't seem to get them to do what i want them to do and am seeking some help from you electronic guru's.

Here is my plan. I want all three switches to light up with a red LED when i turn on my car. Then when i flip each switch, i want a green LED to light up when that switch is on. I'll be using a 2A fuse with one of the switches (not the momentary).


Two switchs i bought are a SPST-Heavy duty Automotive switch (Radio shach # 275-708). Contacts rated 25A at 12VDC. It's a 2 prong switch. The other switch i bought is Heavy-Duty Momentary Auto-flip switch. DPDT contacts rated 20A at 12VDC - Center off (Radio shack # 275-709). It's a 6 prong switch.
The LEDs i bought are red (part # 276-084) and green (part # 276-085). Both have a 100mW power dissipation, 12V forward voltage, and 15mA forward current.
I'm thinking i may need some resistors or something??

 

oh gahh.. i hate radio shack....

the leds you bought are already resistored for 12V.. typical forward voltage for an led is between 2.5-3.5V-ish with 15-20 mA
how you need to hook it up it seems is that for the switch.. it needs to share a common for both leds.. and seperate it so that when the switch is in one position power is going to one led.. and then vice versa..

with those 275-708 SPST POS's... you're not gonna have that happen.. not easily anyway.. maybe use some relays....

the dpdt momentary switch.. i'm thinking hook up the red led on one of the center prongs... send 12V to the other center prong.. and hook it up that way... and then wire up the green in one of the other ones that makes contact with power when the switch is flipped... need to have to jumper for both throws..

gah.. i'm tired.. gonna have to think about the spst's... you should've gotten dpst's......

and i do wonder why you need a dpdt??

besides leds lighting up... what are you putting those switches for..?

 

Thanks for your help. I'll have to look into that. As for the switches, one is being made to turn on my Tuner Pro. It requires a solid power source with an in line 2A fuse on a switch. I don't NEED LED's, but it'd be nice to make sure it has power going to it. The other solid switch is for my NX solenoid that controles my intercooler spray and the momentary on switch is going to an NX purge kit. Rice i know, but my TT's will back that up.

 

You have the wrong switches. What you need is DTDP or DTSP switches.

The ground wire of each each wire is grounded.

The positive wire of each LED connects to the outboard connector of the switch.

The thing you're trying to control also connects to the outboard connector (before the LED) of the green LED - you're forming a parallel circuit where the voltage goes to your engine stuff and the LED at the same time. NOT a series circuit where the power runs through the LED and then into the engine stuff.

The center conductor of the switch connects to the +12V source that you'll toggle downwards to light the green LED or upwards to light the red LED.

 

ok, i'll go ahead and pick up two more switches. My one momentary on switch is correct though right? I still couldn't get that one to work though? I'll have to check it again.

 

Yeah, the momentary switch is a DPDT switch. Don't understand the "center off" on that one. To me that means rather than a push button it's a two way toggle with on-off-on positions with the off being at rest in the middle - think power window up-stop-down like. If so it too is wrong as you'll want a single pole double throw with on/on positions to light the red light normally and when you press it to go green.

 

the reason i got the momentary on (on-off-on) switch is for my purge kit. So i can just pull it down to spray for a second, then release. I COULD use an on/off like my other switches, but that's how i wanted it. Can i still use it, or is there another type of switch that will act in the same manner as my momentary?? I'll have to post pics later tonight. Maybe someone can draw up a diagram or something??