I have just put new batteries into my wii fit balance board and now it will not power on

Put four AA batteries into the battery housing located on the underside of the Wii Balance Board.

Insert a Wii Balance Board compatible game into the Wii system.

Select the "Disc Channel" on the screen with the Wii remote, and choose "Start."

Open the SD card slot to reveal a sync button on the Wii system. This is located behind a cover under the power and eject buttons.

Turn the Wii Balance Board upside down.

Remove the battery cover under the balance board to reveal another sync button.

Pres the sync button on the balance board, then press the sync button on the Wii. Do not hold down the buttons. You know it is synchronized when the blue light on the Wii Balance Board stays steady

Place the board on a flat surface directly in front of the TV. Face the power button away from the TV.

First thing to do is install fresh batteries.If the Wii Balance Board is still experiencing power problems after trying new batteries and ensuring that they are inserted correctly, please call 1-800-255-3700 for assistance


http://www.nintendo.com/consumer/systems/wii/en_na/ts/balanceBoard.jsp

Check the battery levels by pressing the HOME button when playing Wii Fit. the board will be Player Four's battery bars.

i have put in new batteries in my wii board and the lights turn off please help

your board may well need to be synched to the wii again, try that. if the battery pack still rfuses to work, try some AA batteries first, then resynch it. If it still refuses to work suspect your battery pack has discharged and replace it.

All i had to do was SYNCHRO the board by pressing the synchro button on the wii balance board were the battries go, the power LED will blink (note once the power LED has started blinking, stop pressing the synchro button)
THen you need to press the synchro button on the wii console, while the wii balance board's power LED is blinking

According to the Nintendo support site, here's what to do.

Your movements are not being correctly detected

1. Make sure that the Wii Balance Board is placed properly in front of the TV: The blue power light should be facing away from the TV. If the Wii Balance Board is facing the wrong way, your movements will be reversed.
   
   
2. Check the battery life of the batteries in the Wii Balance Board. If the battery level is low, try a fresh set of batteries.
   
   
3. Check to make sure nothing is pressing against the bottom of the Wii Balance Board. If you do find anything pressing against the bottom (such as carpet), try using the foot extensions.
   

If the Wii Balance Board is still not correctly detecting your movement, please call 1-800-255-3700 for assistance.

Here's the link if you want to see for yourself

http://www.nintendo.com/consumer/systems/wii/en_na/ts/balanceBoard.jsp#movement

Guest: Rechargable batteries are only 1.2 V each. You should get up to 4.8 V.

I highly suggest running your Wii Fit on nothing other than Alkaline batteries. I've had my Wii Fit for over 3 months and still use the original batteries.

If you feel like you need rechargables, that's fine, but I recommend a quality set of regular AA rechargable batteries that comes with a quick charger (IE: 1-hour). Stick to the same brand of batteries and buy enough for each Wii-Mote, Wireless Guitar, Wii Fit Balance Board, etc.

Amy - Keep in mind that your Wii Fit balance board will ONLY turn on when your program (ie: Wii Fit) is loaded and ready to go. Since the balance board takes up one of the four available Wii-Mote channels, make sure all but one Wii-Mote is turned off before starting Wii-Fit.

Try new batteries and pushing and holding the sync. button on the wii and the balance board, (that is if you are reffering to the balance board).

If you remove the rechargable battery pack and put regular batteries back in, are you still having the same problem? If so, I would recommend returning the rechargable unit and replacing it.

For what it is worth, I've been using my Wii Fit board for nearly a month on 4 alkaline batteries and have not had any problems.

I recommend rechargeable NiMH batteries with a 15-minute quick charger. Always have four more batteries than you need in your machine, ie: if you have a Wii Fit, a Nyko Wireless Sensor Bar, and two Wiimotes, then you should have 16 batteries total (4 + 4 + 2 + 2 + 4 spare).

Good luck!