Intermittent turn signal failure (first works then doesn't)

My RV is a 1994 33’ Holiday Rambler with a Ford F53 chassis. I have a question about power relays. When I begin a journey I always check my turn signals and brake lights before starting out. Twice now, at journey’s end, it appeared that the turn signals weren’t working. However, later on, after I was settled, I checked the turn signals (and brake lights) and everything was working fine. I don’t know if the brake lights are affected or if the headlights/tail lights are working. I only know that I’m not getting the standard turn signal indicator lights at the dashboard. I normally pull a toad when I travel and use magnetic tail lights with it. Does the circuit have a relay that might be overheating and temporarily kicking out? If so where would the relay be? Is it the TRAILER MARKER LAMPS RELAY in the photo?


Some kind person posted this photo sometime ago. I believe it show’s the same setup that I have on my RV.

I'm planning on a short 160 mile trip to San Marcos TX soon so I can replace my rigs failing engine. The thought of making the trip on a bad engine is stressful enough without having to worry about whether or not I have turn signals (and brake lights).

Steve