How to Replace an iMac Power Supply

Fixing electronics of any kind can seem difficult, and it is no different when it comes to Apple iMac computers. Fortunately, replacing an iMac power supply is a fairly simple task that can be performed relatively quickly with a little patience and the right tools. When searching for a new power supply for your iMac, it's best to first go to a local Apple retailer to inquire about obtaining a new power supply. Alternatively, most iMac power supplies can be purchased online at websites such as applecomponents.com or macproonline.com. This process doesn't require any advanced knowledge of computer repair, so it's a task that can be tackled by most people.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Phillips screwdriver
• Flat blade screwdriver
• New power supply

1. Remove the three casing screws located on the bottom of the iMac screen. Then open the computer up to reveal the inside of the iMac computer. The power supply is a silver, rectangular box located near the screw locations you just removed.

2. Loosen the two outer power supply screws. They cannot be removed completely, but they can be loosened. Now you can also loosen the middle power supply screw by turning it to the left as well. This particular screw fastens the power supply to the display bezel, so you'll want to make sure you've loosened the screw as far as it will go.

3. Turn the middle case screw clockwise, which will release the back cover clamp screw.

4. Disconnect the power supply connector using a flat-blade screwdriver. You want to loosen it just enough for you to pull it out with your fingers. Now that you've taken out the connector, you can take out the power supply cable from the connector by rocking it back and forth until it's loose enough to pull out.

5. Tilt the power supply upwards until it clears the edge of the main circuit board. Now you can take it safely out of the computer and set it aside.

6. Now, to insert the new power supply, push up the supply's center screw with a flat-blade screwdriver. This makes it easier to install the power supply.

7. Tilt the power supply slightly and lower it into place.

8. Connect the black power supply cable and reassemble the computer.

Tips & Warnings

• All "customer removable" screws on the iMac are brass-colored. Do not remove screws unless they are brass-colored or you will void your warranty with Apple. Your new power supply will include an ambient light sensor. If your iMac does not have an ambient light sensor, you will need to remove it from the new power source. You can tell whether your iMac has a light sensor by looking at the bottom of the iMac's display bezel. If there is a small bump protruding from the case next to the middle screw, your iMac has a light sensor.
• Never touch any parts or work inside your computer without first "grounding yourself." This means discharging static electricity by touching the metal surface on the inside of the computer. You also should avoid walking around the room before you've completed your work on the computer and put it back together.

References

• Apple's Power Supply Replacement Instructions