Originally Posted by excel
Could it be because we don't have the same TPM like the US. Works differently from what I remember.
That's EXACTLY the reason. We have FTM (Flat Tire Monitor) Totally different. There is NO sensor in our actual wheels. So as long as you have air in your tires, no sensor will go off. The higher end BMW's like the 5 or 7 Series do have TPMS. The best way to tell is, if your stock wheels have metal valve stems then they have the sensor. Black rubber stems like what you will find on your 128 and/or 135 are NOT sensors. There is "no complaining" because you don't have TPMS sensors.
My moms 550i has metal valve stems which is why I had to order her sensors for her Winter tire set-up from Tirerack.