Question about Oral-B iO 4

Hello :) This toothbrush is supposed to have 4 different brushing modes. There is a button to change the mode ("9" in the manual) which is also fitted with an LED that lights up when the brush needs replacing after about 3 months. I can't work out how to tell which mode is currently on. The manual says that the brush defaults to the first mode indicated on the packaging (there's nothing indicated on the packaging). It also says that the brush resumes with the mode it was in last time. I don't understand how I can tell which brushing mode is being used. Is this a fault in my appliance? Is there a display missing or something?