Anyone ever dealt with this (rear PS brake light)

[The Dude]

I'm troubleshooting and to a point I want to see if anyone has seen this before and might have hints/tips/etc. :

Bought an '07 Flagstaff Super Lite a few months ago and, upon pickup, found that all lights worked fine EXCEPT passenger side brake light/hazard. The taillight is good, but it's like the signal isn't picking up when the hazards or brakes are hit.

> I replaced the bulb.
> I replaced the full taillight assembly
> Checked all wiring connections in the rear and made sure everything is connected as should be.
*Looks like both taillights are wired in series with PS being first/upstream (?)
> I thought it might be the 7-pin connector on my truck, so I hooked it up to 2 other trucks and still have same issue.

I'm to the point that I BELIEVE the issue may be where the 7-pin connector cable runs into a junction box. I've got to borrow an OHM meter and dig into it to see if that is the issue.
But I wanted to see if anyone has been through this and done what I've done and might have more insight to offer.

[67L48]

For an RV set-up, I think your truck is wired like this:

The plug side would be opposite, of course.

Since you're not getting the LH turn signals or brakes, then you seem to have a problem with that line. My guess is that there's a break in the wiring somewhere.

On my pop-up, my brakes became intermittent. I traced the wires back to the axle tube where I found a pinch-point. Over the years, the pinch point caused the wire to fray and short out ... was pounded thinner than my fingernail with no insulation remaining. I fixed it and restored my brakes.

You might have something similar going on. If it's not the wiring in the plug harness, then I'd check where the LH wire breaks out of the main wiring harness to go into the light fixture. It may have got caught in something that's causing it to short out ... or it has been severed altogether.

[Scrapper]

Check for a bad ground from the left brake/turn signal to the frame. Rusty or loose ground connections is the most common culprits.