Circuit description

The steering lock ECM and steering lock motor are integrated into the steering lock actuator assembly.

The steering lock actuator assembly (Steering lock ECM) uses the steering lock motor lock position sensor to detect the lock/unlock position.

The steering lock actuator assembly (Steering lock ECM) is input with a lock/unlock command signal from the smart key computer assembly (Collation ECM) and returns a lock operation signal.

As the steering lock actuator assembly (Steering lock ECM) is not connected to CAN communication, CAN communication with external parts is performed via the LIN communication-connected smart key computer assembly (Collation ECM).

DTC DETECTION CONDITION

Diagnostic codes

Detecting conditions

Faulty part

Diagnostic code output check operation

B2781

When one of the following conditions are satisfied (1 trip detection ⁽¹⁾).

Steering lock/unlock position detection sensor malfunction. ⁽²⁾
Steering lock motor drive circuit short circuit malfunction.
Steering lock motor drive circuit open malfunction.

Steering lock actuator assembly (Steering lock ECM)
Large-scale multiplex communication system for vehicle body [LIN]

No output verification required (constantly detected)

⁽¹⁾	Detects malfunctions when the vehicle is set to IG ON.

⁽²⁾	Judged to be a malfunction when both detection switches are ON at the same time.

Fig 1: Lock/Unlock Sensor Graph

Courtesy of SUBARU OF AMERICA, INC.

Vehicle state and fail safe measures during detection

VEHICLE STATE AND FAIL SAFE MEASURES DURING DETECTION

Vehicle state during detection	Fail safe measures during detection
Steering lock, unlock cannot be performed. This means that the engine cannot be started.	Engine starting is prohibited (Does not perform cranking).

Related current data display and work support

RELATED CURRENT DATA DISPLAY AND WORK SUPPORT

Diagnostic codes	Data monitor	Work support
B2781	Check Sensor malfunction history (Steering lock) Motor driver short circuit history	-