Wireless keyboard won't turn on after changing battery

I had the same problem: the Apple wireless keyboard stopped working after replacing the batteries. After a couple of days of playing around (and, yes, buying a new keyboard - which I will now return), I discovered the problem. It was not with the keyboard or the batteries. It's that, when people change the batteries, they often (and uknowingly) turn off the keyboard's power-button. They do this - I did this - while attempting to remove the batteries from their compartment. I didn't know - it's not obvious - that the keyboard has a power button. It is activated (On and Off) by depressing it (slightly). The button is on the side of the keyboard. It's the round thingie at one end of the compartment that contains the batteries.

I hadn't intended to turn it off - and didn't know that I had - when I replaced the batteries.

To "fix" the keyboard: I pressed the power-button on the seemingly defunct wireless keyboard. Green light flashed. The keyboard probably worked at that point, but I didn't check to see that it did. What I did, instead, was to shut down the computer and unplug the recently purchased (and, happily, now superfluous) USB keyboard. Then I restarted the computer. The wireless keyboard worked fine.

My wireless keyboard wouldn't turn on after I changed batteries. I tried the foil ball and other recommendations. Nothing worked. I thought something had failed or disconnected inside. I flipped it over to look for access to the back and noticed a faint graphic on the exterior of the battery tube.

I had put the batteries in 6 times and didn't pay attention to they way they came out. I reversed them and we're back in business. Green light is on.

I know my way around a spludger, I've changed hard drives, fans & memory in multiple MacBooks and missed the most obvious solution.

If you've given up on your wireless keyboard, give this a try.

If you are having problems with getting an Apple Wireless Bluetooth keyboard, mouse or trackpad from connecting to your Mac (iMac, Macbook or Mac Pro), you can try this. The following mentions the keyboard, but it should work for other wireless devices that have a on/off switch of the contact type (i.e. press on and off, rather than a physical slide switch).

1. Switch off the keyboard by holding down the power button for at least 3 seconds
2. Click the Bluetooth icon in the menu bar
3. Click on “Open Bluetooth Preferences”
4. Your keyboard name will be displayed. Two-finger click on it and select REMOVE.
5. Once the keyboard has been removed, turn on the keyboard by holding down the power button, BUT DO NOT LET GO OF THE POWER BUTTON. It must be held down through the entire process.
6. The Setup Assistant will find the keyboard, so click the name of the keyboard, and then click on “Continue”. Make sure you are still holding the power button down.
7. You will be prompted for the Pairing Code. Type the pairing code on the keyboard and then press return. There will be a slight delay whilst the pairing completes (a few seconds)
8. The keyboard will now be Paired. You can now release the power button.

So just to clarify, the trick is to continually HOLD DOWN THE POWER BUTTON.

Believe it or not, Thin foil in the battery compartment kinda fixed it for me.

This video helped me:

https://www.youtube.com/watch?v=dtKo-DxHSIM

My keyboard is almost 5 years old and never had any issues till now.

HI Jason,

I experienced the same problem with my keyboard and I think I may be able to help. First pick your keyboard up and lightly shake it around. If you here something jossling around inside investigate further to see if the noise is comping from where the batteries are located. They may not be in tight enough to create a circuit. The simple fix is to fold a small piece of aluminin foil into a small square and place on top of the batteries and the screw on the cover as you normally would. Hope this helps. Good luck.

Hey,

JasonBChen,

Have you had any luck yet....??

If not just remove batteries and reinsert them again, then press the button on the other side of the keyboard to repair to iMac......viola it works ......

Hope this help....

Sincerely,

Will

Thank you Dino. It worked for me too. I note that you posted this 8 years ago! Unbelievable that Apple haven't fixed whatever the problem is and we are having to adopt makeshift solutions with tinfoil!

I had this same issue and the foil worked. When I compared the batteries that I was replacing, which I believe to be the original ones, they are about 1 mm longer than a normal AA battery (Duracell) that I used.

Glad it worked! Thanks for your answer!

Hi,

I have seen this rarely on both bluetooth keyboard and mouse. Usually charging or what else has no bad effects.

For mouse, just plug and unplug lightning wire likely revives it.

For keyboard it seems at first it only works when lightning wire is plugged in, not when removed. Rebooting doesn't help.

ANSWER: there's a little power switch on each having green and red to indicate position. Just turn the device off for a few seconds, turn it back on, keyboard automatically detects

Why? Devices are detected when powered on. If for some reason the bluetooth gets (out of range, say blocked by a book or hand) it will not re-detect until a "powering on" is happening.

Same problem. computer told me I was low on batteries. Changed the batteries and it the bluetooth could not find the keyboard, the keyboard wouldn't turn on (no green light).

I tried the pea sized tin foil ball...It worked!! thanks!

All this talk about adding the tin foil ball has made me more careful about the way I insert my batteries into the battery compartment. I think the dropping of the heavy battery into the compartment is causing wear on the metal contacts making them wear away, thus the need for more metal to get the contacts to connect. If you think this is ridiculous, please no silly comments. I'm very careful about the way I insert my batteries into my wireless keyboard. No one ever complains about the mouse batteries needing a tin foil ball. It's always the keyboard. Something to think about. I've never needed to add tin foil to my battery compartment. I think it's because I understand that metal can be stressed.

Also had same issue. Tried several sets of batteries, none worked. Then I told a long narrow flat screwdriver and inserted it into the battery compartment. I lightly scraped the bottom of the compartment to remove and corrosion buildup. (Perhaps a long pencil with the erasure end would work better). Then I replaced the batteries and it worked fine.

Look down in the battery compartment - there is a gray circle plastic piece around the metal contact for the positive battery end. I had the same issue recently. Get something small and long enough to get the plastic piece out and the insert it correctly with the crowned in away from the positive end of the battery. The keyboard also works with this removed.