Small round silver locks: try CH751, R001. I have a different key number at work, will post when I go in.
Trailer brakes: as long as the brakes on the trailer are electric (most common) your controller should work. What controller do you have? Most are rated for # of axles, so as long as yours is rated for 2 axles you should be good. Best way to test the trailer brakes is to pull the pin on the break away and see if the brakes actuate. If not then you’ve got some work to do. If they do, then you need to check the truck wiring. Look here:
It will show which connector is what. With a CHARGED battery in the trailer you can jumper between the 12V and the BRAKE, listen and you should hear the magnets grab the drums. If not then you need to start looking for cut/broken wires. You can also pull off a wheel and drum, pull the break away and use any metal object to see if it “sticks” to the magnet. To,use the break away the battery in the trailer needs to be fully charged.
DVD: look at the TV inputs, there may be two sets. As a rule Yellow is video and red/white are audio left/right. What colors are the inputs on the TV?
2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.