1997 Toyota Supra Owners Manual - Page 105

If you pushed any wrong buttons, "Err" and the number of errors you have made will appear on the display before "SEC" does. Go back to step 2 and try again. If the display returns to "-" while you are entering the code, go back to step 3. To make sure the security code has been accepted, turn the ignition to "LOCK" and then back to "ACC". "SEC" should appear on the display. 4. The three-digit code should be on the display. Push "SCAN". 5. Repeat steps 2 and 3, this time entering your new code. You can use digits "0" through "9". 6. The new three-digit code should be on the display. Push and hold in "SCAN" until the display goes dark. (At first, "SEC" will appear on the display.) NOTICE A tenth error will activate the anti-theft system and "HELP" will appear on the display. The audio system will be completely inoperable. At this time, the anti-theft light also comes on. If this occurs, contact your Toyota dealer. 97