Have a Hopkins impulse brake controller. with pressing on brake will apply full brake pressure to trailer and not proportional to amount of truck brake pressure like it had initially. not sure what

Marvin

• 85242 Answers
• Posted on Jul 28, 2008

SOURCE: 2004 F250 No brakelights/turn lights on trailer

You will need to get a 12 volt test light and check the trailer connector for a voltage signal to the trailer, it may also have seperate fuses under the hood for the trailer lights if the system is factory installed, federal law requires the 2 systems be isolated, if there are blown fuses find the short in the trailer before replacing fuse(s), with no exceptions the short is always in the trailer. Hint, check the fuses 1st.

SOURCE: Wiring Trailer hook ups on truck

• 4 way flat connector
• brwn-tail lights
• yellow-left turn
• green right turns
• white ground

1. 5 way connector
2. brwn tail light
3. yellow left
4. green right
5. white grnd
6. blue back up for surge brakes

SOURCE: tow plug

you have one of two things going on first check to see if the brake light on the left side is shorted out, it will be a 1157 bulb replace it and see if it works looking good does not mean it's good if it has a single contact then it's a 1156 bulb, check to make sure where the bulb socket is that the rubber inside the socket is not worn out and the bulb is shorting to ground. if it is buy a 1157 pig tail repair kit at any Nappa auto truck store or any trailer store. replace it if it needs it. Next if that does not fix it pull the left wheel off pull the drum off and look at the wires on the inside, if they are bare inside it's shorting out if you don't see a bare wire look at the color of the two wires and with a ohm meter and one wire disconnected from that side touch them at the plug and to ground one at a time you should have one wire going to ground one not if both wires going to the left side show they are shorted then you need to replace the wire or the electric coil. if you need more help just ask. If I can e-mail you I can send you a diagram and show you how to test if yo don't know. good luck.

SOURCE: Electric trailer brakes are kicking out due to anti-lock brakes

The ABS will shut off the trailer brakes if it detects a problem. It sounds as if the problem is in the ABS control unit, or the trailer brakes may not be grabbing hard enough causing the trailer to push the truck when you are attempting to stop. This sometimes can be corrected by adjusting the gain up on the trailer brakes.

SOURCE: tbc fault trailer disconnected message 05 f350

check the rear plug on the bumper they are prone to water damage and corrosion, if you unplug the 7-way and four way plug from the body connector and test drive the vehicle this will tell you if the plug is the source of the problem.