Q: Was told that the battery is causing the electronic throttle control to not allow the transmission to go out of first gear

Hello. Thanks for writing in. Any automatic transmission can fail with a bad power supply. The technician may not be wrong, but it may be more in-depth than just a bad battery. If you are not noticing any other issues with the vehicle, it may be the power supply to the transmission shift solenoids, which are responsible for controlling the fluid pressures which changes your gears. The alternator may also be failing to charge the battery correctly. The technician who told you this may have already tested the battery and know that it is the issue. If you feel the need to verify this, have the battery and alternator tested. You can do this at most local automotive parts stores. You can always get a second opinion on the symptoms as well.