I don't much about electronics. I replaced my battery in my TC 2290 and it still doesn't recall presets. The help desk said that possibly the heat from the soldering gun ruined the battery. I've got a radio shack multimeter. Here's what I did. I put in on AC/DC mode, the black probe on the negative and the red probe on the positive and it read 2.95 mv. It's supposed to be a 3 volt. I attached a flashlight battery to the terminals and it lit up. Could it possibly not be powerful enough to hold the presets but still work?