Electric bath ventilation - how to stop it?

I'm in a new rental with electric ventilation model Panasonic FY-13 UGPS 4 D.
The ventilation is noisy and constant. It is not on and it is not on a 24 hour system at present. However the noise is constant in the bathroom the toilet and the kitchen. I have tried in vain to stop it at least while taking a bath so that I don't have to submit to the noise. I have the instruction manual which is only in Japanese, I have tried translating it but still can't figure it out.
I have found this link to the instruction manual
http://www.nationalkankisen.com/d/t/FY-13UGT4D.pdf

It would be greatly appreciated if anybody can figure it out and post English instructions.

That is a very complex vent.

(1) Try the OFF button, which is located at lower left corner. But I assume you already tried that. There are 2 (or more?) modes where simply pushing this button may not work. See below two items.

(2) Perhaps it was programmed. To cancel a program, push the button right above the OFF button. While the light is blinking, press the OFF button.

(3) Perhaps the 24 hour function was set. To cancel it, push the button with "24" written on it for 3 or more seconds.

See if above methods work.

In addition, if the toilet vent is turned on, it will keep running even 24hr. mode is turned off and nothing is shown on the display. Also, 3min. time delay is initiated after turned off(programmable).
The device is used for heating/cooling/dew prevention/clothes drying/all season/winter mode/etc. so master the controller.

Thank you. I tried most of your suggestions and nothing works. The noise is constant although nothing is on, on the display. You mentioned if the vent in the toilet is on then the vent in the bathroom will automatically be on also. Is there a way of turning the toilet vent off?
The noise is driving me crazy. I just want to be able to turn it off like an hour a day or so.

Have you tried contacting your landlord?

If stopped get moldy.
You may have to pay expensive repairing/reform fee when rent over.

BTW, which button pushed?
Really understood all buttons meanings?

If you have cellphone(iPhone or) or tablet PC,
you should find and download free pic(by cam) translate apps quickly.(not only for in this case)
https://i.ytimg.com/vi/06olHmcJjS0/maxresdefault.jpg
http://img.wonderhowto.com/img/64/35/63556847043949/0/translate-foreig...
https://lh4.ggpht.com/PKXQ_tA86KrWMa4aEF43TaOdkfgTs1jMLRgAdoBU5I3eAq6s...
Also handwriting apps,too.
http://a5.mzstatic.com/jp/r30/Purple1/v4/f4/fe/70/f4fe7038-6dfb-420e-5...
https://blog.gaijinpot.com/wp-content/uploads/sites/4/2015/03/kani-rec...

Thank you to all those that tried to help. I ended up switching it off from the main electric switchboard and it kind of reset. I now leave the fan on overnight and before taking a steam bath and switched off the rest of the time. What a relief!

Hello again

I'm getting a U04 error (or message) on the display and the vent makes a much louder noise than usual. I cleaned the filter but the U04 message hasn't disappeared. Am I supposed to remove the whole grid and change a different/bigger filter?
As usual all instructions are in Japanese and aside from using translator I haven't been able to figure it out :-(

Looking at the instruction manual (page 15), it says "U04" means it is time to clean the filter. You need to clean the filter and reset (page 13 of the manual).