Table of Contents
How do I know if my electric trailer brakes are working?
You can indeed test a trailer’s electric drum brakes by directly applying +12V power from a fully-charged battery. You can apply this power to the hot and ground contacts on the trailer’s plug (see photo please) or to an individual brake assembly’s two wires.
How do you check electric trailer brakes with a multimeter?
To determine if a brake magnet has an internal short, touch the base of the brake magnet to the negative post of a 12-volt battery. Then, connect one of the brake magnet wires to the negative lead of a multimeter and the positive lead of the multimeter to the positive post of the battery.
How do you test a trailer brake controller?
Testing the brake controller is fairly easy. Sever the blue brake output wire near the brake controller leaving enough room to reconnect it and then apply the manual slide. Using a circuit tester like the Quickee Tester, part # 3808, you should get output to the controller side of the wire you severed.
Why wont my electric brakes work on my trailer?
First, check the vehicle and trailer connectors for corrosion. If there is a bad ground connection the trailer brakes will not work. Next, check the brake controller wiring. Sever the blue brake output wire, leaving enough room to splice it back together when testing is done and then apply the manual slide.
How do you check the magnet on a trailer brake?
Take a straight edge tool and lay it across the top of the magnet. The edge of the magnet should be parallel to the straight edge all the way across. Any pitting or changes in the magnet’s surface indicate abnormal wear and the magnet should be replaced.
How do you reset a trailer brake controller?
To reset the Pilot brake controller part # 80550 all you have to do is unplug the connector behind it for a few minutes. Doing that will return it back to the factory presets.
How much voltage should trailer brakes have?
If the power output is set to the maximum on the brake controller, it should be getting close to 12 volts. If the brake controller has a leveler knob that isn’t level, it won’t work if it’s titled or turned to the side.
How much resistance should trailer brakes have?
A 7 inch brake magnet should have 3.8 to 4.0 ohms of resistance and 10 and 12 inch brake magnets should have 3.2 to 3.5 ohms of resistance. If the resistance is not as specified the magnet needs to be replaced. You can also check the magnet with a 12 volt battery. Sever the magnet wires from the trailer wiring.
How do you find a short in electric trailer brakes?
Look for a pinched wire, or cracked or worn wire insulation that would allow the copper conductor to intermittently contact the trailer frame and create a short. You will also need to pull the hubs to examine the brake magnet wiring inside the brake assembly, once again looking for cracked or worn wire insulation.
How do you check voltage on electric brakes?
To test the voltage at the highest gain setting, you will want to sever the Blue wire a few inches from the back of the controller. Then, you will want to test the voltage coming out of brake controller at maximum gain setting. You should get around the same voltage as the Black wire, slightly less.
How does a brake controller know if a trailer is connected?
Aftermarket brake controllers send a small amount of voltage along the brake output wire, if a trailer is connected, the magnets in the brake assemblies will create a power draw. This power draw tells the controller that a trailer is connected.
Can you pull a trailer with electric brakes without a controller?
The answer is, no. Electric trailer brakes do not work without a brake controller. If your trailer is equipped with electric brakes, you will need a brake controller to tow.
Is there a fuse for electric trailer brakes?
If the trailer brakes will operate with the manual switch, but not when the truck brakes are applied, check the CHMSL fuse in the fuse box under the hood. The lid to the fuse box will have a legend that will help you locate the fuse. Your trailer brakes might simply need adjusting.
Do electric trailer brake magnets get weak?
Not uncommon for electric brake magnets to short out and be weak. I have seen them where the magnet had worn against the drum enough for the magnet to short out to the drum.
How strong should a trailer brake magnet be?
Troubleshooting Trailer Brake Magnets on 12 Inch Brake Assemblies Brake magnets for 12 inch brake assemblies should have an ohms reading that falls within the range of 3.0 to 3.8. The 3.7 ohms reading on your brake magnets does not indicate that the brake magnets need to be replaced.
How strong is a trailer brake magnet?
The consensus seems to be that each magnet draws about 3 amps. If this is so, then the resistance should be about 4 ohms.
