The battery went dead, and I bought a new one. But I can't install it because the alarm goes off. I've tried everything.
Yes, this can be an issue with the Tundra. You should be able to hook up the battery and hit the unlock button and then start the truck to reset the the alarm. The alarm also should reset itself after 30 seconds once it is tripped. If these items do not work, you may want to enlist the help of a mechanic, such as one from YourMechanic, to assist in the battery hookup and alarm reset.
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