Question: All four jacks quit working as soon as you put pressure on them and they won’t level the trailer. Any suggestions?
Answer: We can offer some thoughts on the subject, with the caveat that we are not experts on electric jacks. Our understanding is that jacks were not meant to be used to level your trailer. They are there to be used as frame stabilizers. You level your trailer first then use the jacks to help stabilize the frame.
Since all four jacks seem to be having problems, we suggest looking at the power source. Do you have the correct voltage and amperage being applied to the jacks? Your owners manual should tell you what the operating voltage and amperage needs to be for proper operation.
If you do not have the correct voltage and amperage, then look at the battery or your 120 volt power supply as a source of the problem.
If you have the correct voltage and amperage, then start looking at the electrical connections. Make sure all the connections are good and tight.
While you are at it, make sure that you pay special attention to the ground(s). Check the fuse that protects the jacks as it may be defective.
Your last solution is to take the RV to a service and repair facility.