[Powerdawg]

Hooked up my trailer brake controller, got a red light indicating the unit has power and knows when the brakes are on. But when I hook up the trailer I nothing else on the controller. Unit states it should give me the settings when trailer is connected. Do I need to wire up another fuse in the box in engine compartment? I did have the harness under the dash labeled "trailer brakes".

 

[Carbeaux]

You may need the relays.

 

[TexFirefighter]

You need a relay they usually have them in stock at the Nissan House its like ten bucks i think. Then you should be good to go.

 

[mjw357]

The tow relays have absolutely nothing to do with the brake controller, just the lighting.

You have power and a ground. The only other connections are the wire from the brake pedal switch and the brake wire back to the trailer.

 

[qapla]

Since I already have the relays I have never checked to see if the harness is connected to the brake light switch or the towing system.

However, I have had a problem with corrosion or dirt getting into the connector and not having a good connection. I usually tap my trailer plug on the tongue before I plug in. When I do this, I never have a problem. If I don't do it, I have had lights not work until I did tap it clean.

You may need to chase the problem down with a volt meter and the assistance of another person.

The problem could be that the wiring on the trailer is not working right. You could check this with a 12v source and powering the brake wire at the trailer connector and listening to see if you hear the brakes engaging.