Turning off the interior motion sensor

When I leave my dog in the 2008 535XI, I lock the door with the key fob, then immediately push the lock button again which, according to the manual, is supposed to turn off the interior motion sensor. It has not been working and the alarm goes off as the dog shifts his weight. There is a reference, page 38 of the manual, which alludes to the alarm not functioning properly when the windows are open. Since I always leave the windows open with the dog in the car, could that be why the sensor is still active?
Thanks,

IIRC if the sunroof is open the IMS wont activate, also when you lock the car and press the button again do you see the little red light turn on once you push it? Im not sure if you have to see it red for 1 or maybe 2 seconds wile holding the lock button.

Edit: In the manual it says it should blink "Flash countinuously" If it still doesn't work them i'm outa ideas.

The red light attached to the bottom of the rear view mirror blinks after pressing the lock button twice, with the sun roof open and with it closed.

I have the same exact problem with my dog too, I've just been manually locking the doors but that would be great if we could get a solution to this.

I have a 2008 535xit with comfort access. I read the owners manual on how to disable the motion sensor. I had my dog in the car and she set off the alarm. Pressing the button a second time does not appear to work. Any other ideas?

Strange. If our dog is in the back seat and I hit the button twice very fast, it works fine. Sometimes I forget she's there and hit the button once out of habit. Alarm goes off as she moves around. I unlock/disable and re-lock/re-enable with two very quick clicks and all is well. Is it how quickly we do the second click?

Yes, I think that it is the speed of the second click and watching the red button light on the mirror.
Instructions are on page 38 of the 2008 manual.

The solution is that after you set the alarm, wait a second or two and then double click the center bmw button and I will see that the clown nose red light will stay lit solid for a few seconds then start blinking again. The owners manual I downloaded from BMW USA in incorrect. It is two quick pushes after the alarm is set, not just one.

Good info here- hope same for Touring