- 1). Locate the two batteries you intend to wire to the Perko switch. One battery will be connected to the engine, and the other will power ancillary objects such as lights.
- 2). Unplug the engine's battery cable from the port on the battery.
- 3). Remove the nuts from the positive terminals of both batteries.
- 4). Turn the switch over and remove the nuts from each of the three ports on the back of the switch.
- 5). Connect one end of one of the battery wires that comes included with the switch to the positive terminal on the engine battery. Run the other end to the port labeled "1" on the back of the switch, and replace the nuts for both the panel and battery terminal.
- 6). Connect one end of the other wire to the positive terminal on the remaining battery and the other end to the port labeled "2" on the switch. Replace the battery and port nuts.
- 7). Run the battery cable to the remaining port on the back of the switch, and replace the nut.
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