After the squirrel incident with chewed wires I took my
H3 truck to Chevy shop. Insurance had agreed to cover the cost. Main issue was headlights not working.

Now they work however when I hook up my trailer, running lights do not come on. Brakes and turn signals work fine. Any clues?

thank you

 

Check the trailer plug receptacle on the H3 for power to the circuits.

 

You should check the connector behind rear bumper cover. Sometimes it's rubbing against the frame till cables are wore out. Check my latest tread, I went all the way in ...

 

Thanks. Guy at the dealership- while doing state inspection figured it was simply a blown fuse