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Battery Switch

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Slow power drain on car batteries happen, even if the vehicle isn't running. Some car devices may be automatically turned on or left activated, and these may eat away at the battery's depleting energy. For all you know, you may be losing those cranking amps while parked for a long while. Good thing there's a battery cut off switch. By interrupting the flow of current running from the battery to the starter solenoid and alternator, this battery switch can stop power drain and maximize the use of your car's battery.

By disconnecting the battery to the electrical system, and the devices that run off it, this kill switch can also make it difficult, if not impossible, for bandits to crank the engine and drive off with the stolen vehicle. Some disconnect switches may even come with keys to prevent tampering.

Here's how you can mount this car battery switch:

Step 1: Unhook the negative battery cable from the battery. Using a box wrench, loosen the terminal's lock bolt and remove this from the battery post.

Step 2: Set the cut off switch near the car driver's seat. The switch comes in various designs (read the manufacturer label for instructions and specs of the switch). You may have to drill holes through the dashboard for screws that will secure the switch frame or for the screw-on plate. After unscrewing and detaching the plate, you have to drill a hole that's the same measurement as the front of the switch. Guide the switch through the backside's hole. After this, you can now screw on the disconnected faceplate. What will secure the battery switch in this case is pressure from the plate.

Step 3: Pull out the locknuts from the two posts, which are found on the switch's rear portion. Use a box wrench to carefully remove the nuts.

Step 4: Use a 2-gauge wire if the length between the battery switch and the battery's positive terminal is more than 8 feet. If it's less than this length, a 4-gauge wire should be used. Measure out the distance between the switch and terminal to find out which wire to use. You then have to trim the wire to the right length using cutters on the electrician's pliers. The ring terminals should be crimped on each end. Next thing you have to do is make sure that the ring terminal has a compatible size with the wire's gauge. The ring should be able to fit over the switch post and the battery.

Step 5: Disconnect the positive cable and starter solenoid from the battery. The locknuts must be loosened at each end before you detach the cable from the posts. You can locate the starter solenoid by tracing the cable from the battery.

Step 6: Hook up one of the wires to the battery's positive post and secure this with the locknut. The other end should go to the cutoff switch's post. Don't lock this with the nut just yet.

Step 7: Disengage the wire that's linking the alternator and starter solenoid. Do this only at the solenoid's end. You have to measure out the wire to see if this will go from the alternator to the cut off switch's post, where the positive cable is connected. If not, then you also have to disengage the end that's linked to the alternator. Use a 14-gauge wire with the correct length, with ring terminals on each end, to change the wire. After this, you can reconnect the alternator to one end. You can now attach the alternator to the battery switch post, held in place with the locknut.

Step 8: Interlace an in-line fuse (200 amps) in the center of the wire. The wire should then be trimmed. Make a 1/4-inch insulation of the two ends by stripping. Attach these to the fuse. (Note: You have to check the instructions or labels on how the in-line fuse should be used.)

Step 9: Attach the second post of the battery switch to the starter solenoid. (Note: The second post is the one that's far from the battery.) Before you can connect them, you first have to do some measuring, cutting, and crimping of the ring terminal's ends of a 2- or 4-gauge wire. To lock the wire in place, you have to tighten the locknuts.

Step 10: Reattach the negative battery cable to the battery and seal this with the locknut.

Test the battery switch. Use the manufacturer instructions as a guide for using it.

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