Nintendo Entertainment System (NES) 72-pin Connector Replacement Guide

If you've ever experienced the death of a video game console, you'll know it isn't pretty. First there comes denial, then grief and anger, and finally acceptance of the console's fate. However, unlike more earthly matters, many of the cartridge-based console systems don't die; they just wear out their connectors. Unless you've inconveniently dropped a sledgehammer on your console, or thrown it from a speeding car, chances are you can bring it back from the dead. Read on, and we'll guide you step-by-step through the infamous blinking screen experienced by long-time owners of the infamous 8-bit Nintendo Entertainment System.

Do-it-yourself NES Console Repair

If you really DON'T want to repair your old NES, we offer the NES Top-Loaders, which play all of your old NES games and never have the blinking problem!

The Problem: A Blinking Power Light On Your NES Console

Everyone has seen it, and everyone dreads it: The Blinking NES TV (note the capital letters there) screen.. You may think your NES is broken, and that all of the time you've spent collecting your favorite carts like The Legend of Zelda was a waste of time and money. You think about purchasing a system on Ebay, but realize that you're taking a gamble buying someone else's used system. Why not take 30 minutes out of your life and fix the NES yourself for around $15.00?

What causes the grey screen/blinking screen/funny-characters-on-the-screen? The problem is actually caused by time and wear on your much-used NES. Over the years, the contacts of the game and the contacts of your NES system are not connecting, most likely due to dirt and oxidation building up on the game contacts and NES contacts. If you've followed our instructions on how to clean your video game cartridge, and you're still experiencing non-functioning games, most likely the 72-pin connector on your NES is on its way out and will need to be replaced, or the game may not have been cleaned thoroughly enough. You might think this would be expensive, but the connectors typically go from around ten bucks to twenty bucks, depending upon the vendor and quality of the replacement 72-pin connector. We offer the NES 72-pin replacement connectors here at Replayed Video Games for $9.99, and these connectors are of very high quality.

With the 72-pin connector in hand and a little elbow grease, you can fix the Nintendo yourself in less than 30 minutes time. Read on if you'd like to find out how.

The Solution: Alcohol, Elbow Grease, a pencil eraser, and Qtips

No, the alcohol is not for anything but cleaning the contacts, and you'd be hurting for certain (think blindness and convulsions) if you tried to consume any quantity of isopropanol, so don't. The image below shows the supplies I used to make the repair to my blinking Nintendo:

Gather Your Supplies

1. Isopropanol
2. Cheap Toothbrush
3. Cottonballs (Qtips work great too)
4. Philips head screwdriver(s)
5. Pencil eraser
6. Super Fine (#0000) Steel Wool (Optional, Not Shown)

Remove the Bottom Panel Screws Once you've got all you supplies in hand, a cleaned off coffee table, kitchen table, or counter, and 30 minutes of free time, the first thing you'll want to do is discharge the capacitors in the NES by turning the power button on briefly and then off again, without the system being plugged in of course. Next, flip the NES over and examine the bottom for the six (6) screw holes as shown in Figure 3. Use a Phillips head screwdriver to remove each of the six screws. Put the screws in a Dixie cup or similar container so they don't get lost in your shag carpeting. Be careful about lifting the NES up after you've removed the screws, as the bottom panel is no longer attached to the top panel. Grasping both the bottom panel and top panel of your NES (so it doesn't fall apart), turn it right-side up and set it on the table.

Check Out the Inside of Your NES

You can now easily remove the top panel of your Nintendo Entertainment System, and voila!...your first, (or maybe not if you're curious like me) look at the inner guts (Figure 4) of the NES, the hardware that has helped provide you countless hours of joy and red eyes from lack of sleep.

Remove the Screws from the Metal Covering

If you own a grounding strap, it would probably be a good idea to ground yourself to a metal portion of the NES to discharge any static electricity that could otherwise harm sensitive electronics. Don't ground yourself to the metal covering over the cartridge ejection mechanism, as we'll be removing this in just a minute.

Now is the minute, and it's time to remove the sheet metal casing covering the cartridge ejection mechanism on the NES. The cartridge ejection mechanism (CEM) is the big black plastic thing where it looks like a cartridge would, and does in fact fit. At this point, observe how the CEM fits flat against the circuit board, and that the front of the CEM does NOT bow out at all. This is an important observation, since once you re-attach the CEM after replacing your connector, you'll need to insure the front does not bow out, or else you may have difficulty getting the NES cartridges to stay down (the proper position) during gameplay.

Note that figures 5, 6, and 7 show the locations of all seven screws. Use a phillips head screwdriver to remove all seven screws holding this covering down, and place them in a Dixie cup.

Do-it-yourself NES Console Repair: Part 2 of 3

Keep On Removing the Screws..

Once you've removed all the screws from the metal casing, and picked up the ones you dropped in your carpet, and in the crack of the couch, you'll be able to lift off the sheet metal covering. Take note however, that one little lip of the metal casing is placed under one of the components (refer to red arrow number 2 in Figure 7 - that is where the metal lip can be found.) You may have to give the metal covering a slight back and forth to get it to come out, but you shouldn't have to force it at all.

Once the metal covering is off, go ahead and set it to the side for now. You'll now be able to see the black cartridge ejection mechanism, the spot of interconnectivity to your world of 8-bit zen. At the back of the ejection mechanism is the 72-pin connector we're going to replace.

Remove the Cartridge Ejection Mechanism (CEM)

Figures 8 and 9 show the location of the screws holding down the cartridge ejection mechanism. You'll need to remove all six of the screws with a phillips screwdriver in order to be able to remove it.

Place the six screws you removed from the CEM in a container separate from the one holding the rest of the screws, so you don't get them mixed up. I didn't eyeball them as being different in size, but it's better to be safe than sorry later when you have a stripped screwhole.

Remember! The CEM was laying flat against the circuit board and does NOT bow out at all when properly seated. Ignore those repair guides that tell you to leave the front screws of the CEM slightly loose so the cartridge holder will stay down properly - they are doing you a disservice by giving you incorrect advice on properly repairing your NES!

The Naked Circuit Board

Removal of the CEM is easy: pull it a little forward, as it houses the 72-pin connector we're interested in, and once it is clear of the connector, you can lift it off and set it to the side for now. Figure 10 shows the complete CEM after removal.

Remove Screws Keeping the Circuit Board in Place

Now that you have the CEM removed, you'll be able to see the exposed circuit board and the 72-pin connector in the back, which is merely slotted into the circuit board (Figure 11).

However, Figures 12 and 13 show two screws near where the power cable and A/V cables come in that should be removed before attempting to unslot the connector from the circuit board. These two screws hold down a metal plate that helps to keep the circuit board in place, and if you don't remove them, you'll have a difficult time getting the connector off of the board, and may damage the board if you do.

Do-it-yourself NES Console Repair: Part 3 of 3

Remove the 72-pin Connector From the Circuit Board

Once the screws holding the circuit board in place are removed, you'll be able to lift the circuit board up, but be careful, as controller wires are still attached to it and could easily be broken if you aren't careful. Take a look at the 72-pin connector, and you'll note that the way the connector is slotted is similar to the way PCI/ISA/AGP cards are slotted in a home computer. Gently pull the 72-pin connector towards the back of the NES, which will remove it from the circuit board. Figure 14 shows the direction in which you should remove the 72-pin connector.

At this time, you may want to take a look at the contacts on the circuit board that were exposed when you removed the 72-pin connector. If they are dirty, corroded, or otherwise, you may want to take some of that (optional) superfine (#0000) steel wool and lightly rub it across both sides of the contacts to remove the layer of dirt/corrosion/oxidation. You'll be able to see the contacts get visibly cleaner when you do this, but be warned: rubbing too hard can wear down the contacts too much, preventing your NES from ever working correctly, so use a light touch. After the steel wool, use a little isopropanol on a cotton ball or paper towel to remove any metal grit remaining on the connectors.

Replace the 72-pin Connector and Give it a Whirl!

By gum, you've done it. You've now got your NES disassembled to the point where it is time to replace the 72-pin connector with the shiny, new, 72-pin connector. What, you don't have one? We'll shamelessly plug one of our products here and let you know you can purchase a 72-pin connector from us for $9.99.

The next step may give you the most trouble, depending upon how well organized you kept everything during disassembly, but it is also the shortest set of instructions we'll give in this article: do everything in reverse, of course replacing the old connector with the new one. When you attach this new connector to the circuit board, make sure it is seated evenly across the board, to insure maximal contact with the connectors on the main board. After you've checked to make sure it is firmly on the board, it is just a matter of replacing all of the screws, starting with the screws used to hold the circuit board down, and then the screws to hold the CEM in place. Once you have the CEM back in place, we recommend stopping here before you completely re-assemble the unit in order to (a) give yourself a pat on the back for not plunging a screwdriver through the circuit board, whether as a mishap or in frustration (b) make sure your games work before you close the NES up (see Figure 16). Be sure that when you re-attach the CEM to the circuit board that it is seatedly properly, as an improperly seated CEM will cause the front portion of the CEM to bow out, and the ejection mechanism will not stay down when you push it down. There is a small portion of the CEM that actually fits under the NES circuit board, and until you get this properly seated, you're going to have the 'bowing' problem. It may take a little effort, but correctly seating the CEM will prevent frustration in having to take your NES apart again after not being able to get the cartridge holder to stay down properly.

Super Mario Bros. 3 was our test cartridge, and as you can see, it works just fine. Hopefully, you were as successful in your attempts to repair the NES. If you'd like to send us a comment on this article, or ask for permission to reproduce it, please send our customer service an email and let us know what you thought, ie was it helpful, did it bore you to tears, did you end up sawing your NES in half because of it, etc.