Power trigger wire location

[slemmer]

Just bought an 05 Sierra CrewCab w/5.3L engine - much nicer than my '95 Sierra Extended 5.0L! Installed aux driving lamps; one wire needs to go to the headlamp to act as the 'trigger' for the relay. Instead of attaching to the headlight lead, I was hoping to find a 12v source inside the cab. I thought of areas such as the radio, or air conditioner button for a "ignition on" source, but each time I hook up the voltmeter it comes up hot w/o the key. Can someone advise which source and the colour of the lead that I can pick from?

 

Thanks

Stephen

[JimG]

In my '03 Sierra, I have a fuse called "SEO" which is for upfitters to add accessories before selling the truck. It's located in the fuse panel on the left side of the dash. I think it's 10A which is more than you'll need - that circuit is hot only when the ignition is on. That's what you need. Just make sure whatever you're adding is appropriately fused. Also, from past experience/frustration, the windshield wiper circuit is another good source to use.

[slemmer]

Thanks Jim, I was able to trace that circuit to a 6-way block for that fuse which was located inside the firewall and left of the brake pedal.