Replace Outlets and Extension Cord Plug




Introduction: Replace Outlets and Extension Cord Plug

About: General tinkerer in many areas

I bought an electric car last year. Seriously, folks, if your commute is reasonable, there are some very good deals to be had on used electric cars. The first round of electric car believers started leasing Nissan Leafs back in 2011. As they are coming off of lease, they are being dumped on the used car market. If you can get over your range anxiety, they are a bargain.

First adopters likely invested the extra $500 - $1000 to install a dedicated 220V level two charging plug at their house. Second-hand people, such as myself, have a harder time justifying that investment. I have been charging my Leaf overnight on the included 110V "trickle charger". I don't have outlets at the end of my garage, so I have to plug the charger into an extension cord.

By the way, my house was built in 1974. Fun fact! Electrical outlets wear out. Sometimes that's annoying, because your phone charger keeps falling out. Other times, it's deadly. See, a funny (it's not actually funny. I'm employing a literary device) thing happens when an electrical connection gets loose. The resistance gets higher as more current tries to flow through a smaller contact patch. Do you know how electric heaters work? They pump a ton of current through really thin (high resistance) wire. Outlets and extension cords are made of plastic. Plastic is really awesome stuff. It's very versatile. It can also catch, impressively, on fire. I don't want that in my garage. Nasty stuff, fire. (also likely a large contributing factor to the evolution of the human brain. True story! Look it up.)

Anyway, apparently my car was drawing too much current for my old outlets and it heated up the outlet and plug. I had to replace them, or risk catching my garage on fire.

Step 1: Find Your Breaker Box, Turn Off the Outlet

Before you even think about unscrewing any outlet covers, turn off the power. Ideally, your outlet cover would be labeled with a circuit identifier which would match up to a corresponding circuit identifier on one of the breakers in your breaker box. That won't happen in this land of mortals, though. The next best option would be if someone helpfully labeled the breakers with something like "bedrooms," or "kitchen," or "bathrooms, SW bedroom left wall, east outdoor outlet, and light switch in the attic". Because it makes total sense for all those random locations to be on one circuit. Since we live in the real world, your labels will not help you. Turn off all of your sensitive electronics in the house, plug a lamp into the outlet you are working on, and turn off the circuit breakers one at a time until you find the one that turns off the lamp. You should immediately label both the circuit and the outlet. Hahaha. Just kidding.

Step 2: Unscrew the Outlet Cover and Outlets

This part should be pretty straight-forward.

Step 3: Remove Wires From Old Outlets

For this style of outlet, this is annoying. The wires are shoved into the roundy holes on the back of the outlet. There is a slot above and below the respective holes. You have to simultaneously shove a flat bladed screwdriver into the slot and pull the wire out at the same time. Don't stab yourself with the screwdriver when everything slips out of your hand. Take note of which color wire goes into which hole. You're going to want to copy that arrangement when you put the new outlets in. Probably. They might have done it wrong. Use an outlet checker before you unplug the old one to see if they did it right. Yes, that is out of order. This is why you read all of the instructions before you start.

Step 4: Screw the Wires Into the New Outlets

Look how shameful that old burned plug is. Select your shiny new plug. My shiny new plug has push-holes in the back so that you can conveniently shove your wires in without having to use a screwdriver. If your situation is similar to mine, those convenient holes are useless. I don't think the gauge of my wiring is that large (small? 12 gauge is thicker than 14 gauge, because confusing relationships make you respect people who understand them more?), but it is too thick to fit in the quick connect holes. Bend the wire into a J hook and put the hook around the screws on the new outlets. (that sentence took 1/100000th the time that the actual task takes, and is 2000 words shorter than the transcript of expletives that will come out of your mouth in the process)

Step 5: Shove It Back in the Hole, Screw It, Test It

I mentioned that I don't feel like my wires are that thick. They sure seem thick, though, when you are trying to bend and shape them by shoving your outlets back into the hole from whence they came. Make sure you aren't shoving things in such a manner that insulation is compromised. Screw the outlets in. Now you have to ask yourself how much you believe you did everything correctly and nothing is touching anything that it shouldn't be touching. Clench your buttocks a little, and flip the circuit breaker back on. No pops? The breaker didn't snap back off? That's good. Now take your tester and plug it into your new outlets. Your tester. Yes, the outlet tester that you have. Seriously, you are working on high voltage stuff here. I should have told you to buy one at the same time as you buy the new outlets. I'm telling you now, and you are reading all the instructions before you start, right?

OK. That's sorted. If the tester shows that your wiring is correct, screw the outlet cover back on. Again, if you are like me, it will be old and inflexible. Despite your best efforts to keep the replacement outlets centered in their correct positions, the outlet cover will still crack when you squeeze it over the top of the outlets. That's how you know you did it right.

Step 6: All Done! J/K, LOL, the Extension Cord Plug

Awesome contemporary colloquialisms aside, don't forget that the plug end on your extension cord also has heat damage. Remember? See, look at that picture. The brass is discolored and the plastic is melted. Luckily, when you are buying your replacement outlets and your outlet tester, you can also buy a replacement plug like the one in the picture. Isn't it cool?

Step 7: Cut the Plug Off of Your Cord

That's not a euphemism. As you can see in the first picture, I have my diagonal cutters positioned. As you can see in the second picture, that first picture was a lie because I actually cut the cord in a completely different spot.

Step 8: Check Which Color Goes Where

Use your multi-meter on the continuity setting to check which color wire goes to which tine of the plug. Your continuity meter. The one in your toolbox. Look again. Really? OK. Buy one when you go to buy your outlets, plug, and outlet tester. This is getting expensive. Are you sure you don't just want to hire an electrician? Also, maybe ask him how much it would cost to wire in a 220V outlet for a stage two electric car charger.

Edit: As pointed out in the comments (and by my dad), Green should go to the rounded ground pin. White should go to the larger neutral blade, and black should go to the hot narrow blade. Also, if I was being extra careful about whether the extension cord manufacturer did this correctly, I should have been checking continuity from the other end (the unchopped one) of the extension cord.

Step 9: Strip Your Wires, Insert, Screw

There is a nice strip gauge embossed in the clear plastic inside of the replacement cord plug to tell you how much insulation to strip off of the individual twisted strand wires inside of your extension cord. Strip off about a quarter of an inch more than that of the outside insulation. Next, strip off the appropriate amount of insulation from the wires inside. I used a utility knife to slice off the outer insulation. Then I used some regular scissors to slowly pinch around the circumference of the inner wires. Around and around until there is a deep enough slice that you can see it, but it isn't cutting through into the twisted strands of copper. Then I put the blades of the scissors into the slice and pulled the insulation off the wires. It won't go as smoothly as my description. Insert the wires into the appropriate holes in the plug. You should know which color goes to which tine because of the last step in this instructable.

Step 10: Screw It All Down

Once the wires are securely screwed in, screw the case closed on your replacement plug. Looks great! Hopefully now your garage won't catch on fire. There are other steps you could take towards this end, such as using sheetrock (gypsum board? drywall? what are the kids calling it these days?) instead of plywood, but that would be a project for another day.

Step 11: What You Might Need

Since you read all of the instructions before you started doing anything, it's fine that I'm waiting until now to tell you what you might need to complete this project.

  • Screwdrivers (phillips and flat)
  • Replacement outlets
  • Replacement plug for extension cord
  • Multi-meter with continuity test function
  • Outlet tester
  • Wire stripper (or scissors and a box knife and a very experienced hand)


  • An electrician
  • Money to pay the electrician

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    2 years ago

    One more comment about connecting wires under screw heads: ALWAYS make sure the wire is wrapped in the direction of the screw tightening down. In the 2nd picture in Step 4, it looks like the 'upper' white wire is wrapped the wrong way. When done like this, tightening the screw can lead to the wire getting smoooshed outward, from under the screw head, rather than pulled in tighter under the head.

    Otherwise, great project! Good safety notices, nice pictures, something that everyone should be able to do. FWIW, I really like to use upgraded outlets that DON'T have the little stabby-port for the wire; instead, I like fixtures that have a plate underneath the screw. Makes it almost as easy as using the little stabby-hole, you don't have to do any extra stripping to get enough length to go around the screw and. you can get really good clamping of the wire under the plate.


    5 years ago

    Nice project. And I do agree with replacing older receptacles for the very reason you mentioned. You should have bought new receptacle plate as well and made it all look new and clean. I have a couple things that I would like to mention. First, make absolutely sure you get the white wire on the neutral terminal, the green on the ground and the black ( actually the hot line) on the smaller terminal. Otherwise it may still work, but is not how a lot of electrical appliances are wired to work. The larger slot on the receptacle is the neutral. The rounded over one is the ground, and the smaller slot is the hot. It is done that way on purpose to allow you to contact the ground terminal first as plugging anything in. Second issue. If your plug is tarnished and looks dark and blackish, but the cord is in great condition, you can mix up a little vinegar and some table salt and put the plug into that solution for a few minutes and it will clean the plug back to near new again. Then use some baking soda and water mixture to neutralize that vinegar solution and rinse with fresh water AND DRY IT OFF. There would be no need to replace the plug if it cleans up nicely. JMHO


    Reply 5 years ago

    Thanks for the comment. My dad mentioned the pin arrangements as well, so I edited that step to point out the color-to-pin relationship. As to the reconditioning advice, I wasn't sure if that would be safe in my case. The plastic around the plug blades was pretty melted. Also, I wasn't sure if the heat had annealed the brass (and whether that is even a problem or not). Thanks again!