What other than the fuse could be causing my rear brake and signal lights from working? The signals when turned on blink rapidly on the dash.
I've checked the 20 amp fuse its fine and replaced it anyway. When I plug my trailer in the lights work on the trailer but still no signal or brake on the rear of the truck.
did you check the bulbs
yah the bulbs are good. I was thinking possibly the flasher relay
The rapid pulsing of the dash indication is read by the vehicle as a burnt out bulb. With a mult-meter probe the connections inside the socket with the signals on and make sure you are getting voltage to the sockets. Usually power is supplied to one side of the lights with a jumper being connected to the other side. If there is a break or bad socket it will cause your problem. Usually a bad flasher will result in the light coming on, but not flashing, but it could cause the problem you are experiencing.
i think you might have one of the bulbs bad inside are any lights on the car brighter than the others. if so it could be shorted inside the bulb it can back feed
did you find your problem
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