A battery back-up is provided to allow the Power Pro to remember Cab assignments,
consists, etc. when the power is turned off. The battery should be replaced with CR-
2032 3 VOLT LITHIUM in about 5 years. The battery should be replaced with the power on if you wish to retain all system settings. Be careful to not DROP the battery on active circuitry if you replace it with the power on. We put a scrap of notepaper over the lower circuit board(s) to prevent shorts if we accidentally drop the battery while changing it.