Why are My Trailer Brakes Losing Power?
Question:
One thing to do to troubleshoot your issue with the brake wiring is to make sure that you are getting power from the vehicle's 7-way to the braking pin on your trailer's 7-way connector. I went ahead and attached the diagrams of the pin setups on different styles of 7-way connectors. If you need a circuit tester, I recommend part # PTW2993PTW2993. It is possible that there are some frayed wiring and some corrosion at the pin location as well. When testing this circuit, it is important to use the manual override on the brake controller instead of simply stepping on the brake pedal. As far as the wire that connects to your trailer's brakes from the trailer's 7-way, I went ahead and attached a diagram that shows the wiring setup for the wiring that goes to both sets of brakes. As you can see, the blue braking wire should not affect the brake lights of the trailer in any way. With that being said, if you are having trouble with the driver's side brake lights, that is a separate issue from the brakes. You will need to go through the process of checking for wire fraying and corrosion in the connector as well.
asked by: Brian C
Expert Reply:
One thing to do to troubleshoot your issue with the brake wiring is to make sure that you are getting power from the vehicle's 7-way to the braking pin on your trailer's 7-way connector. I went ahead and attached the diagrams of the pin setups on different styles of 7-way connectors. If you need a circuit tester, I recommend part # PTW2993. It is possible that there are some frayed wiring and some corrosion at the pin location as well. When testing this circuit, it is important to use the manual override on the brake controller instead of simply stepping on the brake pedal.
As far as the wire that connects to your trailer's brakes from the trailer's 7-way, I went ahead and attached a diagram that shows the wiring setup for the wiring that goes to both sets of brakes. As you can see, the blue braking wire should not affect the brake lights of the trailer in any way. With that being said, if you are having trouble with the driver's side brake lights, that is a separate issue from the brakes. You will need to go through the process of checking for wire fraying and corrosion in the connector as well.
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Brian C.
1/1/0001
One thing to do to troubleshoot your issue with the brake wiring is to make sure that you are getting power from the vehicle's 7-way to the braking pin on your trailer's 7-way connector. I went ahead and attached the diagrams of the pin setups on different styles of 7-way connectors. If you need a circuit tester, I recommend part # PTW2993PTW2993. It is possible that there are some frayed wiring and some corrosion at the pin location as well. When testing this circuit, it is important to use the manual override on the brake controller instead of simply stepping on the brake pedal. As far as the wire that connects to your trailer's brakes from the trailer's 7-way, I went ahead and attached a diagram that shows the wiring setup for the wiring that goes to both sets of brakes. As you can see, the blue braking wire should not affect the brake lights of the trailer in any way. With that being said, if you are having trouble with the driver's side brake lights, that is a separate issue from the brakes. You will need to go through the process of checking for wire fraying and corrosion in the connector as well.