What is this plug under bumper?

As stated, the Tacoma was being towed by a motor home. That's for the lights. Best solution is to leave it.

 

Could it also have been used for a removable winch if on the front? Most likely for towing though.

 

Winch requires larger cables.

 

Much larger and only 2 of them

 

Interesting. No RVs in Hawaii. I've seen them on the mainland towing a small car, I assume for getting around towns while the RV is parked, but I never would have thought someone would tow a truck with an RV.

 

I do with my 93 but have a different plug up front.

 

I remember seeing a guy towing a '71 Cadillac. Those big buses don't' feel whatever you have back there.