ETO actuators in mechanical locking and release systems

The structure of the circuit differs in vehicles with automatic transmission and gear change. To avoid accidental shifting in vehicles with automatic transmission, a fail-safe component – also known as Brake Transmission Shift Interlock or BTSI – must be integrated into the circuit.

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The BTSI actuator is activated by pressing the brake pedal which unlocks the vehicle’s gear lever. If the driver or passenger then accidentally moves the gear lever, the ETO GRUPPE actuator prevents a gear from being unintentionally engaged.

In addition, the actuator has an integrated parking recognition switch. During and after driving, it locks the lock cylinder and keeps the key in the ignition until the gear lever is moved back into park position. This prevents the ignition key from being removed during the drive.