Yaris 2007 remote entry doesn't open (it only closes)

[CTScott]

Originally Posted by nicorac

I've made a little step forward.

I measured the cell battery: 2.9v (ok, with no charge attached, anyway...)
I tried cleaning the button with contact cleaner: no way.

Then a lucky break: pressing the Unlock button twice really quick it worked, all of the times.
When I say really quick I mean really quick, say 2 presses in less than 0.3 seconds.

It seems some kind of security feature

That would make me suspicious of the remote itself. Did you clean both the circuit board side and the rubber membrane side of the switch?