Left Turn Light and Stop Light not working

[CrankinStein]

My truck is a 2007 chevy 2500 duramax and it has a 7 pin connection. All the trailer lights work except the left (driver) side blinker and driver side stop light. The brake lockout also works. Ground is good. The truck lights all work. To start with I checked the bulb (good) and then started tracing the wires back through the trailer and truck. The yellow wire is the left blinker and stop light, and this wire is not getting power at the truck harness. I further traced that wire back to a connection near the truck fuse box. Yellow wire is not getting power here either. All other wires in the bundle are powered properly. I can't find a truck fuse specifically for the left side blinker and stop trailer lights. Does anyone know which one it is covered by? So, I pulled every 10, 15, 20 and 30 amp fuse in the truck and tested them. All tested good. So if no fuses are bad, but just outside the fuse box the yellow wire is not getting power, what do I do? I'm at the end of my electrical knowledge and don't know what to check next. Suggestions, thoughts? Thanks. Any help appreciated.

[CatFan]

On my earlier Chevy, it was fuse 4 in the block under the hood. You should be able to measure voltage on both sides of the fuse without removing it from the block.

[CrankinStein]

I'm not sure which one that is. Is there an easy way for me to post a picture of my fuse diagram in this post?

[pops slowdog]

Are you checking the fuses in the fuse box under the hood or the one in the cab? I'm sorry but couldn't tell for sure from your description.

[CrankinStein]

I checked all the ones under the hood. LOL didn't know there was another one. Could the left trailer blinker be in the other box?

[CrankinStein]

That was it! Thanks Pops. Got the manual out and found the 2nd fuse box, found the correct fuse and it was blown. You guys are the best!

[pops slowdog]

Had a 2000 Chev 2500 HD and a 2001 Burb, both with heavy duty towing pkg.. Both had the trailer wiring + other in the left fenderwell mounted under-hood fuse box. They also had the internal circuits fuses in a fuse box located in the drivers side end of the lower dashboard-open the drivers door and look at end of the dash.

Each had a picture of the fuse layout inside the lid for that location.

[375VTROCKET]

If this problem persists--check your "multi-function switch" it contains cc, turns, brake lites, etc. Mine (99 C2500 HD) went bad and wouldn't work either turn signal (I think it blew a fuse also I can't remember). I could take the cover off the fuses at the door and wiggle or press on the fuses and it would work sometimes. Anyway, it turned out being the multi switch.