My motion plus has been working (pretty much) fine for the past month, but I noticed some problems as others have with Resort Swordplay. But now, in Resort Basketball, it is in constant need of recalibration. It stops the game and prompts to calibrate a few times per game. Haven't found posts from anyone else with this problem.
I haven't dropped the wiimote, I haven't added anything that would cause interference, and it has new batteries.
Any suggestions? Guessing I need to replace it - hopeful that I don't have to.
The only thing I can think of to try would be new batteries. It is possible that your batteries are running low and are thus disrupting the Wii Motion Plus's calibration.
If you put new batteries in and continue to experience problems, I would recommend calling Nintendo at 1-800-255-3700.
I'm glad I can help because the same thing happened to me. The reson ended up being that my new wireless router was messing it up so i turned it of and my game worked again. Hope this helps!
Bluetooth runs on the same frequency that wifi routers of the 108.11g variety use (2.4ghz), some cordless phones also use this frequency. So it might be radio interference, or it could be that the soldered connection between the male wiimote connector and the circuit board in the wii motion plus is shorting. Try using the wii motion plus that's giving you problems on different controllers, and try resyncing your controllers. If the wii motion plus still doesn't work properly, you might need to get another one through warranty.
I've had a problem with my Wii Remote like this before. It constantly said "Please connect Wii Remote" every 5 minutes. It was really annoying and I checked the battery level.(which was 4/4) So I changed the batteries and It worked no problem.
I also get this problem, with both my my motion plus attached controllers. But the only way to make it work is to install new batteries. It's very annoying. A brand new battery is only good for about an hour or two, and then it won't work with motion plus anymore, even though the meter says it's full 4/4 bars. I've tried rechargeable batteries (since going through several sets of batteries per controller per day is ludicrous) but they don't have enough voltage even at full charge to work more than a few minutes before the damned thing starts constantly whining about needing calibration.
I will try some of the suggestions here and report back.
I've figured out what the problem was (for me anyway).
Other 2.4 Ghz devices definately interfere with the motion plus controller calibration. I have a 2.4 Ghz TV tranceiever widgit on top of the TV. If I turn it off, all my motion plus problems go away. Even the Sword Play game stops screwing up. And FYI, your 2.4 G phones, your WiFi router, and your microwave oven all blast/bleed all over these frequenceis as well. Don't have any of them on or near when you try and calibrate the Motion Plus controller.
You are a frickin genius! That worked for me as well. I turned off my router and took my mobile and house phone out the room and I have had no more problems since! Thanks for posting, I was just about to put Skyward Sword on Ebay.
If you have your router set up in mixed b/g/n mode, you may want to change it to mixed b/g mode (turn off n) because n mode uses more bandwidth and is more likely to interfere with your Bluetooth devices (like the Wii remote). Also, if you have not already done so, it would help to set your router to a specific channel (like 1 or 11) rather than have the router pick a channel on its own.
It has nothing to do with your router or your batteries.
It has to do with the sensor's sensitivity, which is too high. It's picking up infrared light from outside your windows (or elsewhere) and this tricks the game into thinking your windows are the center of the screen. When that happens, it slowly calibrates towards your windows (when you swing the sword in that direction) instead of the middle of the screen, which throws the sword off.
So you can either block the light from your windows (or whatever source is emitting the infrared light) or you can reduce the sensor bar's sensitivity. You can verify that this is the problem on the sensitivity adjustment screen by pointing the controller at the window with the sensitivity up (and you should see the white dots).