This is very easy to check and fix.
2019 ford f150 interior lights not working.
In addition some vehicles trims or options you select may not qualify for a z plans.
On an rv style 7 way the stop turn light signals are carried on the pins at the 3 o clock and 9 o clock positions and the tail clearance light signals are carried on the pin at the 11 o clock position.
The exterior lights on your trailer stop turn and tail and the interior lights will usually be fed by different power sources.
The first step is to remove the cover of the interior light that stopped working.
When one or more interior lights stop working and the others still work just fine the problem is usually just a burned out bulb.
Also some dealers may choose not to participate in a z plan pricing.
A z plan pricing information is not available on all ford websites.
Fordparkinglights the problem is a fuse on your for.
Use the owners manual to find the locations of any relays or fuses related to the tow package wiring.
2019 f 150 ford trailer running park lights do not work but the brake lights and the blinkers do work.
Your ford f 150 might have relays related to the tow package wiring and not just fuses.
This may require you to unfasten some screws although many of these covers are literally snapped.