Just a quick question. Aunt's got an 07 Sport trac and has a tow pkg etc. She put one of those lighted Ford emblems/ reciever plug and it acts funny. It plugs into the 4 prong port and works when the brakes are on, the right or left turn signal (I forget which one doesn't make it blink) and is dim with the regular taillights. I just want to know why it doesn't blink when one of the turn signals is on, and does with the other. I would of thaught it would do both and mimmic whatever the taillights do as if an actual trailer was bieng pulled.

 

Probably a blown fuse.

 

This is very common for 3rd bake lights that are after market.

The reason that the park light works, is it is a double fillament bulb, so it essentially acts like a tail light on a trailer. The brake light portion runs off of either the right or left turn signal/brake plug...but not both.

Here I'll break it down. There is 3 wires going to the light bulb in the reciever plug. One is ground, one is either the right or left turn signal/brake, and the last one is the running/park light.

Without installing a little more complicated electronic components this is the way it will act. It could be made to not flash with only one turn signal, or to flash to both but it would raise production costs dramatically.

 

Its quite common on those type of hitch plugs. I have seen all makes do the same thing. Its the reason I ditched mine.

 

I figured it was the way it's supposed to be, but try telling chicks that if you're not 100%. Must be a warranty thing, probably wired wrong they say, what happens when I pull a trailer they say? Like you said Colorado, trailers have more complex things to make it run right. I was surprised the damn thing did more than just light up. Thanks folks.