System Diagram

The steering force of the steering wheel is detected by the torque sensor, and the signal is sent to the EPS control unit. The EPS control unit calculates the assistance torque based on the steering torque signal and vehicle speed signal, and activates the motor to assists the steering force.
To activate the three-phase brushless motor properly, the motor angle sensor detects the motor angle, and sends the signal to the EPS control unit.
The EPS control unit sends the motor load status to the PCM. If the electric load of the motor is high while the vehicle is idling or running at a low speed, the PCM increases the idling speed to avoid engine stall.
The EPS control unit receives the vehicle behavior information from the VSA modulator-control unit.
When the EPS system detects a problem, the EPS control unit stores the DTC, and sends the signal to the gauge control module to cause the EPS indicator to come on.
With LKAS: The EPS control unit assists the steering force when the EPS control unit receives the steering assist request from the millimeter wave radar.

For locations of each component on vehicle, refer to Component Location Index:

Courtesy of HONDA, U.S.A., INC.

F-CAN Communication Data

EPS System Receiving Signal

Transmitting Unit	Signal Name
Gauge control module	Driver's door switch signal* 1 Wiper switch status* 1 System operating state signal* 1
PCM	Engine speed signal Vehicle speed signal* 2 Shift position signal* 2 Service check signal System failure Information
TCM* 3	Vehicle speed signal Shift position signal

*1: With driver attention monitor

*2: K24W9/K24V9 engine

*3: L15BE engine

*4: With LKAS

Transmitting Unit	Signal Name
VSA modulator-control unit	Wheel speed signals System operating state signal System failure Information
SRS unit	Yaw rate signal Lateral acceleration signal Longitudinal acceleration signal Driver's seat belt buckle switch status* 1
Millimeter wave radar *4	LKAS mode signal Instructing current signal

*1: With driver attention monitor*

2: K24W9/K24V9 engine

*3: L15BE engine

*4: With LKAS

EPS System Transmitting Signal

Transmitting Unit	Signal Name
EPS control unit	Indicator drive signal Motor load status Idle control demand Steering angle signal System failure Information Driver attention monitor information signal* 1 Steering torque signal 2 Motor speed signal 2

*1: With driver attention monitor

*2: With LKAS