Troubleshooting Electric Over Hydraulic Brakes On 40 Ft Trailer With Dexter Actuator
Question:
Hello i have a 40 foot with 10k alko drums and a dexter pump. For some reason the brakes have a major delay in them. I have bled them several times and nothing works. The front axle will lock while going forward but not backwards and the rear axle will lock up backwards but not forward. I am really at a loss here. Please let me know what you think thank you.
asked by: Adam D
Expert Reply:
The first thing I recommend is to check the brakes you have on your rear axle. It sounds like they are possibly reversed left to right hand. That would cause the problem you are having with them locking when in reverse and not forward. It sounds like the front brakes are acting correctly since they are designed to allow you to back up without locking up as you mentioned.
Next, I recommend testing the breakaway switch. With the breakaway battery fully charged and the trailer plug disconnected, pull the breakaway switch. If the unit runs and builds pressure, the system is running properly.
If it runs with the breakaway switch pulled but does not work under normal conditions, the issue is either a bad brake controller or the wiring between the truck and the actuator.
If the unit runs but will not build pressure with the switch pulled, the actuator may be defective. If the unit does not run, check the voltage between the white wire and the yellow wire. If the voltage is less than 12 volts, either the breakaway wiring is defective or the breakaway switch is bad.
If the brakes are extremely slow to respond there may be something blocking the lines or possibly the lines are too small, and not allowing enough fluid through. The lines should be 3/16 inch diameter at minimum.
Check the ground wire connections on the trailer. They should not be grounded to the trailer only. They should be connected to the ground wire on the connector that is attached to the battery ground.
1) Detach all wires from the Dexter Axle E/H unit leaving only the blue, black, white and yellow wires. It is important that the unit is disconnected from any other wires going to the towing vehicle or breakaway switch and breakaway battery. Failure to do so may result in a faulty test. Using a 12 volt battery, connect the white wire to the negative (-) terminal of the battery.
2) Connect the black wire to the positive (+) terminal of the battery. The motor should not run. If the motor runs, the unit may be defective. Leave the white wire connected to the negative (-) terminal of the battery. Connect the blue and black wires together to the positive (+) terminal of the battery.
The motor should run and the unit should pressurize. If this does not occur, the unit may be defective.
3) Leave the white wire connected to the negative (-) terminal of the battery. Connect only the yellow wire to the positive (+) terminal of the battery. The motor should run and the unit should pressurize. If this does not occur, the unit may be defective.
4) If the unit checks OK, reconnect the wires leading to the trailer plug and repeat steps 1 through 3 at the trailer plug. If you do not get the same results as before, the problem is in the trailer wiring or the electronic brake controller.
Products Referenced in This Question
Dexter DX Series Electric Over Hydraulic Brake Actuator for Drum Brakes - 1,000 psi
- Brake Actuator
- Electric-Hydraulic Brake Actuator
- 1000 psi
- Drum Brakes
- Dexter
more information >
Product Page this Question was Asked From
Dexter DX Series Electric Over Hydraulic Brake Actuator for Disc Brakes - 1,600 psi
- Brake Actuator
- Electric-Hydraulic Brake Actuator
- 1600 psi
- Disc Brakes
- Dexter
more information >
Featured Help Information
Instructions
Continue Researching
- Shop: Fogatti RV Tankless Water Heater - Gas - Automatic Pilot - 41,800 Btu - Black
- Shop: Hydrastar Electric Over Hydraulic Actuator for Drum Brakes - 1,200 psi
- Shop: Ram Gooseneck Coupler w/ Load Bearing Pin - 8" Adjustment - Round - 2-5/16" Ball - 30K
- Shop: Custom Installation Kit for Curt Overbed, Folding Ball Gooseneck Trailer Hitch
- Search Results: bulldog bx1
- Search Results: bulldog velocity
- Shop: Dexter DX Series Electric Over Hydraulic Brake Actuator for Disc Brakes - 1,600 psi
- Search Results: safety chains
- Q&A: How to Determine Hanger Spacing for Tandem Axle Trailer Suspension with 26 Inch Springs
- Shop: Trailer Hitch
- Article: Trailer Wiring Diagrams
- Search Results: trailer jack
- Article: Trailer Tire Sizing
- Shop: Furrion RV Tankless Water Heater - Gas - Automatic Pilot - 60,000 BTU - 16" x 16" Door
- Q&A: Difference Between Trailer Tire Sizes ST205/75R15 and ST225/75R15
- Video: Timbren Axle-Less Trailer Suspension System Installation
- Shop: Trailer Wiring
- Search Results: bearing buddy
- Q&A: Slipper Spring Hanger Positioning for 7,000 lb Tandem Axle
- Shop: Suspension Enhancement
- Video: Furrion RV Tankless Water Heater Installation - 2016 Forest River Wildwood X-Lite Travel Trailer
- Article: Wiring Trailer Lights with a 7-Way Plug (It's Easier Than You Think)
- Shop: Hub Bearing Kit for Lippert, Dexter, and AL-KO Axles - 3,500 lb with #84 Spindle
- Shop: Fifth Wheel Hitch
- Q&A: Timken Bearing Kit Fitment for a 3,500 lb Axle
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: lug nut
- Video: Choosing the Right Trailer Wiring
- Shop: Gooseneck Hitch
- Article: How to Measure the Bolt Pattern of a Trailer Wheel
on Brake Actuator
