2004 Chevy silverado 1500. Brake and turn ok on truck, but right brake voltage not getting to trailer plug. right turn signal works at trailer plug.

If you're only blowing the fuse while the trailer is plugged in, the problem is in the trailer/wiring. This takes into account that the truck has a factory installed 7 way receptacle. If that's not the case, the problem can be in the incorrectly wired truck and the trailer is ok.

On the truck, looking into the 7 way receptacle should be as follows.
Top left=Tail Lights
Top right=12v steady source/charge line
Left middle=Left turn/brake
Right middle=Right turn/brake
Left bottom=ground
Right bottom=brake controller output
Center=reverse lights if your trailer is equipped.

Your trailer plug should mirror this.

This is the standard.

Stop lamp circuit discription

Stop Lamps
The STOP LP 25-amp fuse in the underhood fuse block supplies battery positive voltage to the normally open stop lamp switch. When the driver presses the brake pedal, the switch contacts close and battery positive voltage is supplied to both the STOP 15-amp fuse and the center high mounted stop lamp (CHMSL) 10-amp fuse in the instrument panel (I/P) fuse block, and to the turn signal/hazard module. The turn signal/hazard module then supplies voltage to both of the trailer rear turn/stop lamp supply voltage circuits. The voltage from the CHMSL 10-amp fuse is to the CHMSL and the trailer jumper harness. The voltage from the STOP 15-amp fuse is to the stop lamps, throttle actuator control (TAC) module, and the cruise control.

I think The turn signal/hazard module has something to do with the lights flashing .From looking at a wiring diagram B+ voltage from the STOP LP fuse 25amp in the under hood fuse box supply's the brake light switch , from there it feeds B+ to VEH STOP fuse 15amp and VEH CHMSL fuse 10amp an to stop lamp switch signal to the turn signal flasher module which is suppose to control the trailer stop lights . Do you have a connection for a trailer hook up ?
Remove both LT an RT TRLR fuse's both 10 amp from the I/P fuse block an see if the problem goes away .

Do you tow a trailer ? Check the trailer connector for corrosion !

Chances are the trailers bulbs need to be replaced. The truck uses the same wire for turn and brake signals. If they work on the truck, That means there is something wrong with the trailer.
I wrote a great article about diagnosing trailer problems. Click here to read.

if they camper was wired for an older/other make of truck it might be different check to see if the yellow(left side turn/brake) wire maybe connected or crossed with the green(right turn/brake) wire,also see if the plug in wiring under the rear bumper is a stock plug in or if some one tried to go cheap and use"scotch-locks" on the tail light wires and crossed something under there,the parts store sells a plug in tester for your truck's particular plug that will tell you if the truck has the issue or if it's the camper,also check the ground,hope this helps,and good luck

It sounds like you lost a ground.
check traier hookup first.
Probably not the controller.
P.S. There are multiple fuses for this setup. check all ! ! !

Have you checked the fuse box under the hood? There are seperate fuses for the truck lights and the trailer lights. If the fuses look good use a 12 volt test light to check for power on the turn signal pins when the brake is pushed. The brake lights and turn signals use the same wires to work. Power here would indicate the wiring and fuses on the truck is all good, meaning the trouble is on the trailer. Check the bulbs to be sure they are the correct ones, they should be dual element bulbs. Make sure you have a good ground on the trailer, usually the white wire in the 4 way plug is grounded to the trailer frame, do not depend on the trailer ball to be the ground, this is asking for trouble.

check fuse under hood, batery terminals coroded wire at harness if everything fails run a hot wire to rear brake line with an interuptor.
check the swich under the foot brake.
vitally

Check under hood fuse box make sure L. trailer light fuse isnt blown.

you prob got a trailer plug prob bad wires if not tail lights run through turn signal switch tell fix ya bout me ok

so, the trailer has no brake lights, or turn signals, just tail lights? Everything (all lights) on truck work ok? What do you have for trailer wiring hook up 4, 5, 6, or 7 way? There is no fuse, the lights all work off the tow vehicle lights, so if the tow vehicle lights all work properly, it's probably a wiring problem, such as bad grounds, loose connections, etc. Get a volt meter and check voltage at truck plug to see if power is getting that far. If truck plug in is ok, wiring problem is the trailer. Make sure all grounds are tight and rust free, that's a common problem.