A catalytic converter theft protection arrangement includes a metal cage rigidly attached to an underside of a vehicle such that the cage surrounds a catalytic converter of the vehicle. An electronic tamper-detecting device is disposed within the cage and transmits an alarm signal in response to detecting motion around the catalytic converter and/or vibration of the cage. A remote controller selectively activates and deactivates the electronic tamper-detecting device in response to actuation of the remote controller by a user.