jeeper31

I just foound a 12v flashing LED that I want to install to make the car look like it is alarmed. I am going to install light in one of the empty switch spaces in front of the shifter. I am going to splice into the cig lighter because I think that is always powered. I would like to use the switch for the rear wiper (my wiper is deleted) to turn the LED on and off. Is this possible? What wires should i splic into? IS there a better way than using the cig lighter?

Thanks

jmporsche944

Cool idea.. If your going to put it in the empty switch space then the cig lighter is probably the best source.. or the radio, that would work too. I dont know about the wiring though sorry.

Techno Duck

Not sure about the cigarette lighter, but you can also use the constant power lead of the radio. It always has current as its what saves your radio station settings...etc.

jeeper31

You guys are right. I am thinking the radio wire might be better and easier. Now i need to know how to incorporate the switch into it. Anybody??

Techno Duck

Well its nothing special, just splice the switch inline with the positive current wire. So basically...


LED ------> Switch ------> Radio power

jeeper31

Since the switch is already grounded am I just hooking both wires of the LED to the switch and then one wire from the switch to the radio power?

(Just so have you know I am not totally dense I did put my whole stereo system in myself including amp and sub. so just being a little dense)

83na944

THe switch is already grounded? Do you mean that there is a wire running to ground from the switch and a wire running to the fuse panel?

One thing to remember is that LEDs are polarized. Be sure to identify the right lead by looking at the wiring diagram.

jeeper31

That's what I am assuming.

Chris_924s

I've been looking for one, where did you find it Dan?

BTW- congrats on selling the old 944!

jeeper31

Found it at a local store named AMP something. If you can't find it I'll pick you up one and send it to you.

Chris_924s

Auto parts?? I'll check around- Thanks!

SDGuy

Why not install a keyless entry/alarm system for real if you are going to the trouble. I just put one in my 86 NA last week and it rocks. Putting actuators in the doors was much easier than I thought it would be.

I did put the alarm led in the very spot you are referring to. Looks great there. If you have your heart set on your flasher, get an automotive relay and have it tripped with 12v ignition while the car is on (so the LED is off). Then, when the car is off, the relay sends 12v to the led - so no switch/remembering required. Relay is standard Bosch type with:

pin 85 to ignition 12v
pin 86 to ground
pin 30 to battery 12v
pin 87a to + side of LED
The (-) side of the led goes to ground. Make sure the LED is a 12v type or you will need a resistor. I'm giving these directions off the top of my head, so no warranty- check you circuit yourself and refer to this bosch relay diagram: http://www.classictruckshop.com/club...osch/relay.htm
ps - the switch next to the mirror switch is a switch to lock and unlock the doors while driving. The alarm I got has ignition switched door locking - a very nice feature. The doors unlock on turning off the ignition.

jeeper31

Not auto parts was an electrical store. Has wires, circuits, capacitors, transistors... all that electrical stuff. Let me know.

DanG

I have a blinking led set up almost exactly like the picture SDGuy posted. I bought the LED, LED socket, and switch from Radio Shack. The LED I bought was clear when off, with a blinking red light.

Keep in mind most LEDs are not rated for 12V. If you just wire them up strait, you'll blow them right away. Use a calculator like this...

http://www.bit-tech.net/article/68/

...to figure out the correct Ohms of resistance you'll need to keep things in check. The resistor will drop the voltage across the LED to the typical 1.7-2.4V that most can handle. They do make 12V LEDs, but most of them are the ~2V variety. Check the specs on whatever LED you buy, as they do vary a bit.

http://www.kpsec.freeuk.com/components/led.htm

Is another good site that runs through the basics for you. Remember, the shorter lead on the LED is the (-) side, connect that to ground.

I actually used a resistor greater than the calculator told me, I found that with the LED at max voltage, it was so bright it would light up the whole inside of the car. You could see it from across a parking lot. I thought it was too bright, probably atracting so much attention that it made itself useless. Its alot more intimidating looking with it turned down a couple notches. As you walk by the car and peek in the window, its just there in front of the stick, blinking away.

Of course, I don't have an alarm to back it up, but who's gonna know.

Porsche-O-Phile

Just pull the coil wire if you're parking the car somewhere questionable. I've done that on numerous occasions. It takes all of ten seconds to do and unless the bad guys have a flatbed, they're not getting the car. They'd likely just give up and go elsewhere.