Trailer disconnected in dash.

[Hoverp]

So I bought a trailer that was wired for a f150, and uses the 7 round light plug. It has electric brakes and every thing works great other than the truck doesn't know the trailer is connected when it's plugged in. I get the " trailer disconnected " warning in the dash when I apply the trailer brake on the dash.

All any idea ? What contact in the 7 round tells the truck that the trailer is there?

Thanks!

 

[Bulletnjm]

Bad fuse?

 

[Hoverp]

This trailer has electric brakes , no battery, so the charging fuse would not need to be installed, I was wondering what pin on the 7 tells the truck the trailer is connected?

When I use the manual brake on the TBC it displayed the warning and the trailer brakes don't work..

I'll double check all wires.

 

[The Car Stereo Company]

did you put the relay and fuse in under your hood?

 

[Hoverp]

No sir I didnt, from reading here and elsewhere that the fuse and relay was only there to charge the trailer breakaway battery , which mine does not have. Is it required to have those in to make the connection so the truck knows the trailer is back there?

 

[The Car Stereo Company]

yes. it makes all the lights work too.

 

[Hoverp]

My lights did work without it installed!

 

[The Car Stereo Company]

interesting. but that fuse and relay will make the brakes work

 

[Hoverp]

Ok I'll put them in, I just went out to the truck and got them out of the glove box. " Hey there made in USA"

What fuse slots do they go into ?

 

[The Car Stereo Company]

shit....... i cant remember off the top of my head. it is in the owners manual. it took me a while to find it, but it is there