I replaced the RTC battery in my Ruby cart but it still says the battery is dry. I tried using 2 different batteries, both show the same problem. I measured each with a multimeter and they read ~3V. I measured all around the solder contacts with it after putting in the battery and it also shows the same thing. Did the heat from the solder fry something? It's a 60W iron which might be too much for circuit boards... The cart is authentic as far as I know.