Batteries & Electrical

Wiring and Soldering Tips

Take control of the electric gremlins in your car.

Dodgy wiring, inadequate fusing and exposed connectors could lead to a fire.

The most reliable way of joining two wires together is by soldering; it’s the act of using heat, via a soldering iron, and a fusible metal, the solder, to create the electrical connection.

The other safe connection option is the crimp connector – being simple and easy to use they are popular, however, don’t always offer the longevity of soldering. When using crimp connectors, always ensure the connector has been crushed enough to create a tight connection. You don’t want the wire coming loose over bumps or through vibration.

Make sure you select the correct gauge wire and fuse for your application. An accessory drawing high current, with small wiring and inadequate fusing will almost certainly cause a fire. Determine the current draw of the accessory in amperes (amps) and select the appropriate gauge wire. From this, you’ll be able to fit the correct size fuse - as the fuse is there to protect the wire from the excessive current draw.

What you need

  • Wire strippers
  • Soldering iron
  • Solder
  • Heat gun
  • Heat shrink

Step 1 - Prepare Wires

Step 1

Before you start, ensure you disconnect the battery before soldering, and any carpet or plastic trim is protected from molten solder.

Strip off approximately 1cm of insulation from the end of each wire to be joined and slide a 3cm piece of heat-shrink over one piece of wire.

Step 2 - Twist Wires Together

Step 2

Hold the two ends in an ‘X’ shape and twist one wire along the length of the other wire. Repeat to create a strong, but efficient connection.

Step 3 - Join Wires

Step 3

With the soldering iron heated up, sit the end of the solder over the joint. Apply heat from underneath until the solder has flown through the joint.

If the solder does not flow through more heat will be required.

Without moving it, let the joint cool. You should have a nice shiny finish on the solder and be able to see the outline of the individual wires, but not any exposed strands.

Step 4 - Protect Joint

Step 4

After you are satisfied with the joint, slide the heat shrink over the top and apply heat to seal.

Heatshrink won’t come unstuck as electrical tape will.