How to Replace a Battery Isolator
- 1). Move the vehicle to a well-ventilated area. Use the wrench to disconnect the black negative wire on both batteries.
- 2). Loosen all three wire cable clamps on the battery isolator terminals. Remove the charging cable clamp first. This is the cable that runs back to the alternator. Swing that wire over to the new charging terminal on the new battery isolator and tighten it into place.
- 3). Check the documentation supplied with the new battery isolator to identify which terminal should connect to the starting battery. Once that terminal is identified, remove the red starting battery wire from the old battery isolator and connect it to the new isolator. Tighten it and move to the final connection.
- 4). Remove the wire, which connects to the second battery, from the old isolator. Connect it to the second battery connection on the new isolator. Tighten it and use a screwdriver or wrench to remove the old screws or bolts that hold the old isolator to the engine bay wall. Remove the old isolator.
- 5). Move the new isolator into the position of the old one and use new screws to secure it to the engine bay wall.
- 6). Reconnect each of the black negative battery wires and test the sound system by turning it on without the engine running.
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