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Symptom: Pump motor runs, Jack(s) do not move

RVA Diagnostic


When the pump motor runs but the jacks do not move complete the following steps.
1.) Have a test light ready at the corresponding extend valve for the jack that is not operating. When you are ready have a helper press the extend switch for that jack and verify that you are getting a good ground and 12 volts to the coil of the extend valve.

a. If you are getting ground and 12 volts to the extend valve coil then have a ferrous metal coat hanger near the coil and see if you have a magnetic pull.

- If you do not feel a magnetic pull there, replace the coil and retest the system.
- If you have a magnetic pull then the coil is good, and the problem is hydraulic related, and you will need to go to Section 3.

b. If you are not getting 12 volts to the extend valve

coil then complete the following steps.

2. Verify the wiring of the extend valve.

a. If no voltage is found on the coil when the extend switch is being pressed for that jack, test at the back of the switch to see if you have 12 volts
into the switch.

- If there is 12 volts present, press the switch and see if you have 12 volts out of the switch.

- If you have 12 volts out of the switch then follow the wires back to the controller. Refer to the wiring schematics.

- Test on each side of every connection as you follow the wires through. If you find a connection that is failed replace the connection and retest.

3.) Check for an extend valve failure.
a. The affected extend valve can be exchanged with a valve from a jack that is working properly. If the problem follows the affected valve then replace the valve.
b. If the problem does not follow the affected valve then the extend valve is not failed.

4.) If all of above checks out, then reinstall the valves back into the original position and retest.

a. If the jack works after reinstallation of the valve then there may have been some debris in the system. It would be recommended to install a new extend valve as there may be damage that will cause the same issue again later.