Electrical Cord Repair

 Electrical Cord Repair

Using a continuity tester to check an attached power cord. Make sure the appliance’s switch is on.

Cords on appliances, tools, clocks, computers, printers — anything that gets its power through an electrical outlet — can malfunction. Knowing how to fix electrical cords is important to knowing how to fix lots of things in your home. This Fix-It Guide on electrical cord repair tells how an electrical cord works, what often goes wrong, how to identify an electrical problem, and what parts and tools you will need to fix it. It then gives instructions for how to test an electrical cord, how to replace an electrical cord, how to strip an electrical cord or other electrical wire, and how to replace a flat-cord electrical plug or quick-connect electrical plug. Electrical cord repair may be required to complete paper shredder repair, pasta maker repair, power tool repair, small appliance repair, and many, many other household repairs.

How Does an Electrical Cord Work?

A cord is a small flexible insulated electrical cable with a plug at one or both ends that connects an electrical device with a source of electricity. There is a wide variety of cords, each with wires and plugs designed to carry a specific electrical load.

What Can Go Wrong with an Electrical Cord?

Cords and plugs can break. Through repeated use, they can develop shorts and stop delivering electricity to the item that needs power. Fortunately, they are relatively easy to test and repair or replace.

Fix-It Tip

Most small appliances use two-wire 14- or 16-gauge cords with two-prong plugs. Heating appliances (iron, toaster, space heater) use heavy insulated wires. Grounded appliances use three-wire 12- or 14-gauge cord with three-prong plugs. Large appliances (range, air conditioner, clothes dryer) use three-wire 6- or 8-gauge cord with special three-prong plugs. As you can see, the lower the wire gauge number, the greater the electrical current it can carry.

How Can I Identify an Electrical Cord Problem?

Electrical Cord Repair

Using a continuity tester to check a power cord that’s removed from the appliance.

Frequently, problems with appliances, tools, and other electrical devices can be traced to the cord or plug. Test it for continuity (see below) and replace if faulty (see below) before completely disassembling and testing the device itself.

If the plug of an electrical device shows obvious damage, you can replace it without replacing the entire cord (see below) — just be sure that replacement cords and plugs are of the same type and rating.

Because the function of an electrical cord is to deliver electricity to the device, you’ll be testing it for this trait, called continuity.

Fix-It Tip

Lamps and smaller appliances use flat-cord plugs. Cords on electrical devices typically are manufactured with and sealed to the cord. Quick-connect replacement plugs are easy to install but won’t stand up to repeated plugging and unplugging because they are not sealed to the cord. Medium and larger appliances and devices typically use round-cord plugs, often with a third prong for grounding the circuit. Some heating appliances use detachable cords. If you replace a detachable cord, make sure the new cord is of the same power rating and prong configuration.

What Do I Need for Electrical Cord Repair?

You can buy replacement cords, cord wire, and various prongs at larger hardware stores. The tools you need to test and replace electrical cords include these:

  • Multimeter or continuity tester
  • Screwdrivers
  • Wire stripper
  • Wire connectors

What Are the Steps to Electrical Cord Repair?

Test an attached 120-volt electrical cord:

  1. Unplug the appliance or device.
  2. Disassemble the device to access the cord terminals. Un-clip, unscrew, or de-solder the cord’s connectors from the device. If there is a loop or strain-relief fitting, remove it.
  3. Set your multimeter on RX1 (resistance times 1) scale. Or you can use a continuity tester.
  4. Clip a jumper wire across the cord leads (or twist the two wires together). Clip or touch the meter’s probes to the plug prongs. The meter should read zero ohms.
  5. Bend and pull on the entire cord. A steady zero-ohms reading means the cord is okay. A high or fluctuating reading means the cord is faulty and should be replaced with an exact duplicate.
 Electrical Cord Repair

Touch probes to the plug prong and one of the female plug ends to determine if there is continuity.

Test a removable electrical cord for continuity:

  1. Unplug the appliance.
  2. Set the multimeter on the RX1 (resistance times 1) scale. Or you can use a continuity tester.
  3. Clip a jumper wire across the male plug and insert the test probes into the female plug.
  4. Bend and pull the cord along its entire length. If the meter reads zero ohms (no resistance to the flow of electricity), the cord is good. A high or fluctuating reading means there is an open circuit. Replace the cord and/or the plug.
 Electrical Cord Repair

An infinite reading on the multimeter indicates that there is a break in the cord–or that you’re not testing both ends of the same cord wire.

Test a 240-volt electrical cord:

  1. Unplug the appliance.
  2. Unscrew and remove the terminal block cover plate, found where the cord enters the electrical device. If there are any signs of damage, replace the block. If the block is okay, test the power cord.
  3. Set your multimeter on the RX1 (resistance times 1) scale.
  4. Clip the meter probes to the plug’s outer prongs.
  5. Clip the jumper wire across the outer cord terminals.
  6. Bend and pull the cord. Replace the cord if the multimeter reads above zero ohms or fluctuates.
  7. Clip the jumper across the middle and one outer terminal, then clip the multimeter to the corresponding plug prongs. Look for steady zero-ohms readings. If readings fluctuate, replace the cord and/or plug.
 Electrical Cord Repair

Some power cords are imprinted with their specifications. This one says “18AWGX2C” meaning there are two 18-gauge wires.

Replace an electrical cord:

  1. Unplug the appliance.
  2. Remove the old cord.
  3. Remove insulation from the new cord if necessary (see below).
  4. Connect the new cord leads to the appliance leads or terminals.

Strip an electrical cord or other electrical wire:

  1. Insert 1/4 inch of the tip of wire into the corresponding hole in the jaws of an electrical wire stripper tool.
  2. Close the tool to cut and remove insulation from the end of the wire.
  3. Verify that the insulation is cleanly cut and removed from the wire.

Replace an electrical cord:

  1. Unplug the appliance.
  2. Remove the old cord.
  3. Remove insulation from the new cord if necessary (see below).
  4. Connect the new cord leads to the appliance leads or terminals.

Strip an electrical cord or other electrical wire:

  1. Insert 1/4 inch of the tip of wire into the corresponding hole in the jaws of an electrical wire stripper tool.
  2. Close the tool to cut and remove insulation from the end of the wire.
  3. Verify that the insulation is cleanly cut and removed from the wire. If not, repeat the process using a larger or smaller gauge hole in the stripper tool.
 Electrical Cord Repair

You can purchase various replacement plugs such as an easy grip plug (top left), a trim fit plug (top center), or a flat handle plug (top right) at hardware stores and electrical suppliers.

Replace a flat-cord electrical plug:

  1. Unplug the electrical appliance or device.
  2. Use a wire stripper or wire cutting tool to remove the old plug from the cord.
  3. Unscrew or otherwise open the new plug to expose the contacts or terminal screws within the plug.
  4. Feed the cord’s wires into the new plug, and tie a knot in the wires to ensure that pulling on the cord in use will not pull the wires from the plug terminals.
  5. Remove (strip) insulation from the cord’s ends and attach them to the plug’s terminals, following the replacement plug manufacturer’s instructions.
  6. Reassemble the plug and test for continuity before use.

Replace a quick-connect electrical plug:

  1. Unplug the electrical appliance or device.
  2. Cut the old plug from the cord. Do not separate or strip wire ends.
  3. Pinch the prongs of the new plug and pull out the plug core.
  4. Feed the cord through rear of the shell. Spread the prongs apart and insert the cord into the plug core.
  5. Squeeze the prongs together to pierce the cord’s wires. Then slide the plug’s core back into its shell.