The Prius is extremely quiet, so pay attention to the instrumentation to know if it is running. Some newer model cars will not require that you insert the key, as long as it’s in the vehicle.
In later generation models of the Prius, this function will not display ODO and this method will not work. You may need to press the button more than once to make it display the letters “ODO. ” Turn the vehicle off the letters “ODO” appear.
Be sure the engine is off before attempting to start it again.
Count to ten to yourself before letting go of the button. If the display changes you can let go.
The reverse beep may still sound at this point.
Turn the car off again. The next time you start the car, the reverse beeping will be disabled.
If you have difficulty repeating the process, take the vehicle to your local Toyota dealership and they can reactivate the reverse alarm for you.
Some Bluetooth OBDII adapters are designed specifically for certain smart phones, so be sure to purchase one that works with yours. Android phones may be better for this specific application.
If you are having difficulty locating the OBDII port in your Prius, refer to the owner’s manual to assist you in locating it.
Make sure the adapter is seated firmly in the port so it has a strong connection. Press the start button without your foot on the brake to engage the car’s electrical system.
Open the application and create an account if need be. Turn on Bluetooth on your smart phone.
You may need to open settings and tell the phone to sync with the adapter. If you have a Bluetooth password on your phone, you will need to enter it for the two to connect.
Some phones may be unable to access this menu. If that is the case, you will have to edit the code yourself.
You can go back in and change this setting again any time you want. After changing the setting, close the application and remove the adaptor from the OBDII port. If you ever decide to turn the reverse alarm back on, simply change the setting back to “on. "
There may be other options available to you for download. Ensure the application you choose allows you to manually input lines of code to interact with the car’s computer.
Be aware, modifying the code in your vehicle’s computer may cause other issues and should only be done by professionals. Doing this may void your warranty if you have one.
Enter the command “AT SH 7c0” and the vehicle should respond, “ok. ” Type “21ac” and the response should be “61 AC 00” which represents the reverse horn setting. Enter the code “3bac40” which will adjust the setting. You will receive two lines of code from the car indicating that you are done.
Close the application once you have verified the new setting is in place. Start the vehicle and test to ensure the backup horn is off.
The price for this service may range from $50 to $200 depending on the availability of the tools needed and the dealership itself. This is the safest way to deactivate the backup horn.
Enter the command “AT SH 7c0” and the vehicle should respond, “ok. ” Type “21ac” and the response should be “61 AC 40” which represents the reverse alarm being set to off. Enter the code “3bac00” which will re-activate the alarm. You will receive two lines of code from the car indicating that you are done.
