P0633 P0633 code definition The P0633 code is triggered when the vehicle's PCM (Powertrain Control Module) or ECM (Engine Control Module) is unable to recognize the immobilizer key (https://www.yourmechanic.com/article/how-a-keyless-push-button-ignition-works) (https://www.yourmechanic.com/article/how-a-keyless-push-button-ignition-works). What the P0633 code means P0633 is cued when there...
