trailer left turn signal not working PLEASE help

[4Runner_101]

so when i plug my trailer into my 2010 4runner the left turn signal and brake does not work, when trailer is plugged into my friends chevy it works fine. last year everything worked with my 4runner but now for some reason the stupid left turn signal and brake light dont work. they work on my tail lights, but not on the trailer, i checked all the fuses and there good, took the plugs out and wd-40'd it and still no luck. Its been driving me crazy,Anyone know what it could be? thanks

 

[JohnJerk]

Had a similar problem on my '11 and I had a blown fuse in the engine bay which I replaced and that fixed the problem. Seems you checked those fuses already unless you were referring to some on the trailer. Good luck.

 

[4Runner_101]

Had a similar problem on my '11 and I had a blown fuse in the engine bay which I replaced and that fixed the problem. Seems you checked those fuses already unless you were referring to some on the trailer. Good luck.

Ya checked all the fuses under the dash and hood, there all good