I am trying to wire a temp gauge and have 4 wires. One ground, one for illumination, one for ignition and one for battery.

Why would I need to hook into all those seperate power sources? If I want the gauge to operate while the say the lights are on or while the ignition is on wouldnt I just get the power from that source.

Say I want the lights to only operate when the ignition is on. Would I just connect all 3 wires to that source?


Sorry for the stupid questions. I have read every post on wiring I can find and dont understand why I ned all those power sources.

 

You either have them labeled wrong or didn't list them all. One goes to the ignition circuit because your temp gauge doesn't need to display anything with the car off. One goes to the battery source because your instruments WILL lights up without the key. One goes to ground because 12 V electrical circuits need one. The last one goes to the temperature sending sensor - because what good is all that power to the gauge if it doesn't know how hot the car is?

 

My greddy has 4 too
Ground: Ground of course
illumination: Hooked up to something that turns on with the lights
ignition: something that gets power when the key is in the on postion
battery: go to the battery, maybe for the sensor, who knows dont ask.

search next time please
~Luke

 

Wire it up like they want you to. I know Greddy gauges really don't like having the battery lead hooked up to switched - dunno why, but that's the deal.

The illumination wire is so the gauge lights up when you turn your lights on, otherwise the gauge would be lit all the time. It is better to have the gauge light up with the headlights, since there are some conditions where having the gauge lit in the daytime makes it harder to read. Also, if it's hooked up properly to the lighting circuit, the gauge will dim as you dim the dash lights.

Dale