What prevents the engine from shutting off after a remote start when the brake is applied?

The correct answer is that a defective stop lamp switch prevents the engine from shutting off after a remote start when the brake is applied. In many remote start systems, the engine is designed to remain running until the brake pedal is pressed, at which point it should typically shut off unless the correct conditions for continuation of operation are met.

The stop lamp switch is responsible for activating the brake lights when the brake pedal is pressed. If this switch is faulty and does not signal that the brake has been engaged, the remote start system may not recognize that the vehicle should shut off. This can lead to the engine continuing to run even after the brake is applied, creating a potential hazard if the vehicle is in gear or in an unsafe position.

In contrast, other options describe components that may affect the starting or running of the engine but do not directly relate to the shutdown process triggered by brake application in the context of remote start systems.