You need a meter, measure battery voltage with no load, should 12 volts or more. Now with the meter still on the battery, try the jacks, or the slides, not both, and watch the meter. Should still be 12 volts. Now connect the meter to the motor, and check voltage while trying to move the jacks OR the slides. Should be over 12 volts. Any reading of 10 volts or less is too low. If the voltage is good, next would be to remove the motor from the pump, and see if it will run. Run for a few minutes, and see if it gets hot. Depending on what you find here is where you go next.
Never assume voltage is good. You must have a meter. Could be corroded cable, bad relay, number of things.
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