Recently bought a very nice low-mileage 2008 128i convertible (US model).

There are times I'd like to be able to leave the car doors unlocked (so someone won't slash the top to get in) but have the trunk locked.

I'm aware of the valet switch in the glove compartment, but I just can't seem to get it to work as described. For testing purposes, is there also an additional interlock on the glovebox being open and/or locked as well as putting the switch in the glovebox into the lock position?

I'm not using the glovebox switch for valet purposes, I'd just like some way to have the doors be unlocked and have it not be possible to open the trunk with either the button on the lower left of the dash or the button on the trunk lid. Not sure if the glove box switch really even matters for this specific requirement, seems to me that I've been able to get the trunk to open with the button on the fob when the switch was in the lock position, which is why I'm wondering if there is a glovebox switch interlock that may be flaky.

Seems like this should be simple, but I can't seem to find the magic sequence.

Thanks for any suggestions!