If too many keys and or fobs have been installed, what are my options to start over again?
Every time you program your keychain remotes it starts over and you must program ALL of them. This is a security feature so someone cannot go and add a remote to your vehicle without your knowledge (your remote would not work if they didn't have it to reprogram it). So, go through the steps all over again, only programming the maximum number of keychains (I don't know what that number is). Here's a link for a detailed tutorial on programming them: http://www.shareyourrepair.com/2014/09/how-to-program- keyless-entry-remote-for-2004-2010-toyota-sienna.html
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