Theory Of Operation

The Electronic Steering Lock (ESL) Module prevents the Steering Wheel from turning when the Ignition Switch is in the OFF position or when the Immobilizer System does not receive the correct security code. A Lock/Unlock Motor inside the ESL Module incorporates a locking mechanism that locks or unlocks the steering wheel. The ESL Module communicates with several Electronic Control Units (ECUs) through the Controller Area Network (CAN) Bus network. The Anti-lock Brake System (ABS) Module provides a Vehicle Speed Signal to the ESL Module by way of a CAN Bus message. The Vehicle Speed Signal is used by the ESL Module to determine if the conditions are correct to lock the steering wheel. The Body Control Module (BCM) transmits the Lock/Unlock commands through CAN Bus messages to the ESL Module.