Hardwiring F750 to fuse panel - can't find ACCessory only fuse

[DarkSky]

I have an '07 Chevy Avalance LTZ.

I checked all the fuses with voltmeter when the truck was off - everything showing 12V I put a black mark on the fuse with a sharpy.

I started the truck up, and then went with the voltmeter on all the other fuses - they STILL showed ZERO volts. !!??

I need to find at least one fuse that is powered ONLY when the truck is on. Of the maybe 15 fuses, there's about 10 that show 12V when the truck is off and keys are out, and the rest still don't show anything when the truck is running (or keys turned to ACCessory).

What am I doing wrong?

 

[jokiin]

does the vehicle have two fuse panels?

 

[DarkSky]

does the vehicle have two fuse panels?

Yah.. there's another under the hood. I'll probably have to search there. And drill holes and hope I don't drill into something expensive on the other side...

Strange that out of all the fuses in the panel that's in the cabin of the truck, none are "only when the truck is on" power.

 

[jokiin]

Check the owners manual, there may be another panel

 

[Ralph2]

How.. are you checking for voltage? The "buss" has a hot side and a cold side and the fuse bridges them to complete the circuit. You need to check both sides to a common ground to find which side is "hot". Typically.. the radio fuse is a good one for getting switched power and the brake for an always on source.