Trailer light check

I noticed yesterday that when lock the Tacoma and the lights flash they do on the trailer as well. I think I will use this to do a quick light check every time I hook up a trailer.

Is the flashing light on the brake light circuit?

 

The blinking lights are on the Blinker/Brake Light circuit. So it won't test your running lights, only turns/brake lights.

 

Yes the running lights are connected once you plug the trailer in

 

But can't be tested by clicking the keyfob.

 

A modern 5 wire trailer is mirroring your 5 wire truck. If there's an adapter, a 5 to 3 wire then brake lights to turn signals. Anything you plug into your trailer harness will flash or be on when the truck has voltage on those wires.

 

Ok so if I hit the fob and the trailer blinks I have brake lights

 

yes, it's an easy method to test if you don't have someone or something to push on the brake pedal