This should get stickied.

 

disconnect battery...disconnect BOTH positive and negative or just Negative for approx. 10 mins?

I'm a bit afraid because last time I disconnected my battery (both positive and negative) It somehow fried my maf sensor and that sh*t cost me $160 for a new one...I'm having the sunroof issue....so i need to fix it.

 

ive been having that problem just like you for 3 years. I have done that Re-learn thing, but didnt work. hate the noise but got to deal with it, the next noise i hear is with the roof open, i hear as if a bolt is loose and washer is vibrating. Cant see where it is.

 

Just the negative one. Let it sit for a minute and then re-connect the negative terminal. Open the sunroof part way and then close it holding the switch, even after the sunroof is fully closed, until you a loud click and you should be good to go.

You'll have to reset the windows too but no whistle.

 

Thank You, Thank You,Thank You!!

I have had this stupid whistling for months and re-initializing worked for me too, I just wanted to post to say that it worked for me without disconnecting the battery. I just opened the roof all the way and then closed it all the way and held the button for about 15 seconds. I actually did it while it was making the noise and you could hear it seal and no more squeal!! wooo hoooo... haha I'm way too excited

 

Man I'm so glad I looked this up was about to go to Toyota/Scion in the morning about that moonroof. I've had my '05 tC for about 4 months and the whistling noise was annoying me thanks for the quick and easy fix