Those would be turn signals, hazards and the brake lights which run through the switch. That's one of the quirks of that vintage, the rear lights are normally both turn and brake lights to to make them work the switch does a few things. When you select hazard lights it connects all 4 corners and pulses the power to them. But say you are turning right and coming up to a stop sign. If the turn signals were connected to both ends in the same way you would turn on the right side and get hazard lights, or step on the brakes and have the front turn signals come on as well as the brake lights.
Now if this RV is set up with individual rear lights it might be a bit simpler but in that year most were not. Think you could get a shot of the rear of it and one from the side, that might help narrow down which chassis it actually has. I don't know of anyone but the class A rigs that used individual lights but RV builders are in a class of their own when it comes to confusion. Some just add a builders connection block that they connect to the up-fitters connections, Others like to re-wire half the chassis to suit them and use odd color codes for all of it, even though they start with a commercial chassis like a GMC van or mid sized truck. The attached were the common versions, the first two used the same chassis as do the last 2 That is why they are not real easy to ID as they mixed a lot of parts around.
The colors you posted sound like they match the #1997966 switch which was used in the value van and base level units, but it's in a tilt column like the higher option vehicles.
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Tuesday, March 9th, 2021 AT 5:40 PM