The owners manual is useless. Look at the appliances and get model numbers and go to the site of the company that makes each appliance. You will never find a wiring diagram because they do not exist for the consumer. A 26 year old camper has probably had many modifications to it. As much as I think there is a lot of misinformation on it, Youtube is good for some things. Start from the top down and look for things like how to inspect sealant on the roof and windows, inspecting for leaks inside and checking running gear and tires. Some manufacturers have videos on how to check and maintain their products. Just don't expect much support from the original trailer manufacturer
On edit: Include the power center as an appliance. Make sure you have no 120 coming into the trailer before you pull the unit out to check the model number.
2020 Keystone Cougar 22RBS, Ram 1500, two Jacks and plenty of time to roam!
The difference between genius and stupidity is that genius has its limits. A.E.
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