I’ve narrowed it down to the left blinker. What would cause the fuse to blow instantly upon activation? I’ve downloaded the EWD FSM and will dive in but, damn. I don’t want to mess with this. Chasing electrical gremlins is not a strong suit of mine. Tips?
Check trailer wiring.
Pull the bulbs and check fuses.
Insert bulbs one at a time, check fuses.
You might want to look at the harness under the jack, look for blue/green oxidation as this can short the system. Easiest if you remove the jack holder.
At least the front turn signal bulb is plugged into a pigtail that's about 6 inches long, which is itself plugged into the engine bay harness on that side. I can't remember if the rear is too, I think not. I'd check the condition of the connection between the harness and pigtail first. You'll need to remove the turn signal housing to see it. IME, it's the bulb socket that usually fails first. You can replace the pigtail for a couple of dollars.
The rear harness segment is more expensive, but I've not seen one of those fail (arguably, I haven't seen every 80 in North America...)
If you have a short somewhere, it'll likely be easy to see, and if not, twisting and/or bending the wire (a little) at the connection should expose it. If you're not having other electrical failures, it's most likely near the bulb.
I know electrical troubleshooting isn't the most fun exercise on the planet, but a cheap multimeter will set you back less than $20 and will find continuity problems, which is what a short (or open) circuit is. It's no harder than chasing down a burned out Christmas tree bulb used to be.
Sorted this out finally. It was the aftermarket trailer harness. Took that crap out hooked everything back up like it wanted and have normal, legal blinkers again.
