not sure if it still applies, but on the 2001 camry, you turned the key (in the ingnition) frpom off to on 3 times in 3 secs, and then the security light would turn on, and if you pressed the horn and then after the security light flashed u turned the key back to off. it used to turn on the toot as u locked/unlocked. Thats going off memory tho searching for my file with all the camry hidden settings. plus that was 01 model they may have changed it for the aurions will update if i find this file