Dump Trailer Troubleshooting

Please use this page to assist in Troubleshooting with your Dump Trailer.

Warning: Operating your dump trailer without first understanding the proper operation procedures can lead to injury or death.




On a Power Up / Power Down system, a low battery will cause hydraulic fluid to leak into the pump box during cycle operation on the down stroke and can cause electrical components, like the trailer's charge line, to burn out. Items burned or melted caused from a dead battery are not covered by warranty.


Voltage operation range is 12.8 to 12.0 DC volts. If Battery drops to 10 volts or lower during the operation cycle operation, it will close the down valve and cause the fluid in the cylinders to pump back into the reservoir instead of back into the bottom of the cylinder. This will cause the system to overfill and leak out of the breather / fill cap into the pump box.

Pump Wiring Troubleshooting

Before testing the wiring and controls, make sure your dump trailer’s battery is charged to at least 12.0 DC volts. If there isn’t a battery load tester to test the battery, depress the test button on the battery charger to check the battery charge state. A DC voltmeter, 12 volt tester or power probe is required to test the dump trailer properly.

If the Pump Does Not Run:

  1. Start by connecting the test light’s ground clamp to the negative battery post. Touch the point to the positive post to make sure the test light lights up.
  2. Now, touch the test light to the dump trailer solenoid. The positive battery cable light should be on.
  3. The pump motor should run when the up or down button is pressed while touching the small brown wire at the motor solenoid. If the light does not light up on one or both buttons, either the controller input voltage (typically the black wire) is missing, or the push controller is bad.
  4. If the above tests are okay, touch the large terminal opposite the positive battery terminal on the motor solenoid. If the test light lights up and the motor still does not run, and there is certainty that the battery voltage is normal, the pump motor has lost its ground or the pump motor is bad

If Pump Runs but Box Does Not Go Up or Down:

Warning: a low or under-charged battery will allow the pump to run and sound normal, but will not allow enough power to activate fluid solenoids to allow them to open the up and down valves properly. If the battery voltage is low, the trailer will go up but will not come down even with the pump motor running.

Recheck the battery state of charge before assuming the pump on the dump trailer is bad.

  1. Check all small wires and ensure they are connected to the small fluid control solenoids. Check the small gray wires leading away from the two fluid solenoids and make sure they attach to a solid ground point.
  2. While pushing the up button, probe the terminal at the green wire (Carry-On) or red wire (Interstate). If the light is on, the solenoid is getting power.
  3. While pushing the down button, probe the terminal where the blue wire (Carry-On) or green wire (Interstate) attaches to the dump trailer fluid solenoid. The light should illuminate.

If both wires are lighting up and the box still does not power up or down, please call us for further assistance.

If you have any questions outside of what is covered in this Troubleshooting guide, please call us at 314-416-1117.


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