We have 2016 Salem by Forest River pull camper. The two slide outs and hydronic.jacks will not go in. Have checked all fuses even 12V50 amp on frame. Any ideas?

In the link

https://www.google.com/search?q=breaker+box+in+Salem+T27DBUD

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I've had RV's with fuse/breaker boxes just inside the entry door and my motor home has vehicle fuses under tip up dash, RV fuses (breakers) near floor under fridge.

The Rockwood is manufactured by Forest River. Contact your nearest authorized retailer or click here: Forest River RV Contact Us Forest River Inc

go to a transfer station and weigh it,we r fixya,not your scale

RV manufacturers do not generate an owner's manual such as you would see for a car. They do issue a very generic one for all trailers they manufacture and you can download the latest from the Forest River site. Appliances which are installed have owners manuals as well from their respective manufacturers. I suggest you get on one of the forums for Forest River and your type of trailer and ask fellow RVers any questions you may have. This is the best way to get specific guidance on your trailer,

It should be near the floor - look for a brown or black square - the circuit breakers may be behind the door - you may have to turn the black plastic pieces 90 degrees or you may just have to pull down on the cover. Instead of circuit breakers, I think they used automotive fuses. There should also be a fan in there that runs when the AC is plugged in to cooler the rectifier.

If the bed is on the slide, more than likely the mechanism is under it. If not then it should be outside in the under belly.
I would check for voltage at the switch first.

some more details would be nice. Do a wild guess is it mechanical or electrical?