A Trane thermostat has the ability to have the keypad locked. This is extremely beneficial in situations where you do not want other people to change the settings on your thermostat. After being locked for a period of time, you may have forgotten how to unlock the thermostat when you want to make changes to the settings. It can be very frustrating that something so simple can keep you from making the needed changes to your thermostat.
Examine your Trane thermostat. Find both the "+" and "-" buttons on it.
Put one finger on the "+" button and one finger on the "-" button. Press both these buttons simultaneously.
Hold these buttons down for four to five seconds and then release. The Trane thermostat should now be unlocked.