Troubleshooting HydraStar Electric Over Hydraulic Actuator Running But Not Pressurizing

Updated 12/02/2019 | Published 11/30/2019

Question:

Trouble shooting? No pressure when pump is clearly working? Also while break away not connected

asked by: Steve

Expert Reply:

There are a few things you can check on your HydraStar Electric Over Hydraulic Actuator # HBA16 if it is running but doesn't actually build pressure. This could potentially be an electrical problem or issue with the motor. It's also possible that the issue is coming from the brake controller you are using in the cab.

I would first make sure that the actuator is properly grounded. The ground connection needs to be on the vehicle and not the trailer. Make sure there isn't any rust or corrosion that might be preventing a solid connection.

I would then try to test the unit by using a 12V battery to apply power directly to the unit. Disconnect it from the tow vehicle and the breakaway system (which you have already done) so that it's isolated from any other power source. First connect the white wire to the negative terminal on the battery and the black wire to the positive terminal. At this point the motor should NOT run - if it does then there's an internal issue and it will need to be replaced/repaired by HydraStar.

If that checks out okay next leave the white wire connected to the negative terminal but connect the blue and black wires together to the positive terminal. At this point the motor should run and start to pressurize. If not then there's again something internal going on that needs to be repaired/replaced.

If it works correctly then the issue is coming from the trailer wiring or the brake controller. Make sure your brake controller is set to electric over hydraulic mode and that it's compatible with the HydraStar actuator. If you are using a factory integrated brake controller an adapter might be needed. Just let me know what model truck you have if this is the case and I can see if one is needed.

expert reply by: Chris R