Disconnect the negative battery cable from the battery.
Remove all wires from the solenoid terminal studs. There is no need to remove the solenoid from the frame.
Connect an volt meter, set on continuity, to the two large terminal studs. The meter should indicate no continuity, if there are only two large terminal stubs. Replace the solenoid if continuity is present.
NOTE If the solenoid has four large terminal stubs, one pair will have continuity and the other pair will not. When energized, the readings will be reversed.
Using jumper cables, attach the correct battery voltage (6 volt solenoid needs 6 volts applied, 36 volt solenoid needs 36 volts supplied) to the two small solenoid studs, polarity is not important. You should hear a click as the solenoid engages, and the meter should indicate continuity on the two large terminals. Replace the solenoid if voltage is not present.
When finished, replace all the wires and connect the negative battery cable.