iMac Intel 20" EMC 2133 and 2210 PRAM Battery Replacement

isn't it actually pc2-5300s ?

At this stage and later handling the LCD I found thin cotton gloves helped to reduce smudges

My GPS unit's car mount suction cup worked nicely here - couldn't find any at the store and didn't want to wait for mail order!

Two cups would make it easier but one is fine if you place it in the center and are careful to pull the panel straight out.

Why use suction cups when some finger nails will do the job nicely, though a plastic spudger might work too. Start at a top corner. Prize the glass away from the case and leave finger nails in. Move the other hand along the top edge and then with finger spread peel the screen cover away. Be careful not to twist plastic I suppose, but I've had no difficulties.

3M Command Strip hooks in opposite corners is another fabulous option when suction cups are not available!

Tape works fine, here. Search for a YouTube video for a simple look-see.

I didn't have any suction cups, but my pencil sharpener (the kind that suctions to the table) worked great. I put it on the middle and lifted straight up.

For a quick 'n' dirty alternative "tool" for this step, take a look at IKEA's Stugvik suction hooks: they provide an excellent adjustable grip. Just used it to take apart an EMC2133. Cheers!

Suction cups usually available at Home Depot or Lowes, in the flooring section. (They're used to handle large ceramic & stone floor tiles.)

In order to avoid unnecessary smudges and what not I covered the LCD itself with some plastic wrap while doing the hard drive upgrade. When I reinstalled it all I needed to do was blow off a few dust particles.

While you are at it, it is worth cleaning out dust within the case to help with cooling - particularly around the fans and vents.

For the screen I used a lens cleaner from my camera bag. These have very fine fibers and won't leave detritus.

Note that the front glass panel is quite light. When reassembling I found it impossible to get the LCD free of dust with the computer lying on its back. I had success with standing the computer up, tilting the LCD down as far as it goes, holding the glass panel upright in front of the computer (about 1 foot away), lightly spraying both the LCD and the back side of the glass panel with compressed air, and then attaching the glass panel (with the computer upright). It took me 5 tries before it was completely clean of dust once the front glass was on.

On the 24" EMC2134 there are 3 screw sizes: 6x13, 4x20 & 2x30mm, particular note should be made of their location.

Note for the less experienced.. the case is plastic and the metal coarse thread screws will easily cut a new thread in the hole if you don't line up the screw in the original thread. Do this a few times and the hole will be stripped and the screw no longer tightens.

TIP:- place the screw in the hole and rotate BACKWARDS/counter clockwise (for RH threads) until you hear/feel it click/drop into the original thread then tighten the screw down. rotate it a couple times to get the feel of things. If there is any significant resistance you probably don't have the original thread.

This trick also works on the fine metal thread screws and can help avoid cross threading them.

HIH

On the 24 inch iMac Model A1225 EMC #2134, the two T8 Torx screws in the middle are the longer of the four total bottom 25 mm screws. Just a note for reassembly.

This step is not really explained here with pictures. But you can check this same step in another guide to help you : iMac Intel 20" EMC 2266 Front Bezel Replacement

I'll echo Thibault's comment. This guide does not actually tell you when and/or how to remove the bezel! Click on the other guide he linked to see the photo and instructions.

Make sure you're ram slot at the bottom is open to remove front frame bezel

I think you're missing this step: With the iMac lying on its back screen facing up, grasp the aluminum sides of the bezel and carefully pull it straight up. Then disconnect the microphone cable. Took me a while to figure it out.

I found it helpful to use a few lids from spaghetti sauce jars to hold the different screws. I used a sharpie to mark the inside of the lid w/ location taken from or the step number from directions. Then I placed a small magnet under the lid to hold the screws inside the lid in case I accidentally jostle something on the table. Worked great! You can also use a magnetic knife bar to line up the lids in sequential for the project.

I avoided this step by just flipping the housing over and having it lay flat on the table. The tape on mine was on really tight, and I risking ripping the wires out of the connector if I messed with it (I didn't have some really small scissors which might have helped removing it). I would suggest either securing the body of the iMac and the housing to the table you're working on, or somehow securing the housing to the body, so that it doesn't move around accidentally, since it's only hanging on by a very thin wire at that point.

Make sure you do not pull this apart by the wires. Have a firm grasp on the plastic parts. Do not force back together. It only goes back together one way. Also, it is crucial when placing the aluminum bezel back in place that this wire is out of the way. It often gets in the way and is easily damaged.

CAUTION - To disconnect the cable, you'll need to support the bezel while you carefully extract slack microphone cable which is tightly tucked within the iMac. (I didn't have this guide's 'notes on' and missed robgendreau's warning - then inadvertently shifted the bezel and busted my microphone cable in this step.)

Don't forget to pull the microphone cord out before you put the panel back on. Otherwise you will have to go back and remove screws to find that microphone cord

As robgendreau says, avoid this whole step by opening the bezel and laying it upside down above the iMac, still connected by the mic cord, just carefully. Then replace the battery, suck/blow out your dust, and carefully rotate the front bezel back over the iMac from where you removed it. No cord manipulation or damage at all!

Note that when you replace the PRAM battery, the system date is reset to 2004.

After rebooting, verify if the date needs to be adjusted.

Mine did not reset to 2004, or else reset itself correctly later before I looked at the date.

I suggest keeping your finger firmly over tab on the right side of the battery holder. It is extremely thin and must have become very brittle from heat and age. When the battery was pushed towards it and then pivoted up from the left, the tab snapped and pivoted up with the battery. Super glue and reinforcement time.