2000 GMC 1500, is there an unswitched hot between the cab and the bumper?

Factual Questions
1

Arcane question, but the title says it all. I want to install a 12V port in the bed to use occasionally. I know that the pinout for a 7-pin RV connector has 12V auxillary power on one of the pins, but this truck has a round 4 pin trailer connector.

If there isn’t one, then I probably won’t install the port, since I don’t want to run a single wire from the dash or fuse panel. I didn’t find power at the gang terminal, but that may have just been me not being on a good ground. The wiring hasn’t been touched since it left the factory, and I’d rather not peel back the looming to check each wire without knowing that a hot is there.

2

If no one answers here, try a specialty forum–for example:

3

Thanks. I’ve found that the specialty forums can be hit or miss unless you know where to go. Thanks for the recommendation.

4

Does the 4 pin connector have a pigtail that terminates at a connector? Finding that connector may be worth your time, there a chance that all trucks are wired for 7 pin at the rear of the truck at the connector.

5

Very smart! I’ll check it out.