I have a 2008 Honda Pilot in which the buttons on the key to unlock and lock the doors would have to be pressed a few times before it would work. A few days ago it quit working completely so I figured the battery had died. Well, I checked the voltage on the battery and it was just under 3 Volts, so the battery should be fine. I replaced it anyways and it still doesn't work. My other key locks and unlocks the doors fine. After changing the battery does the key need to be resynced with the vehicle? Any idea what is wrong? Thanks.

 

Most likely a bad transmitter Module. If one key works aND Not the other we can rule out a bad antenna/Control unit IN vehicle. Battery voltage is good/new there is only 1 thing left.