System Description
SYSTEM DIAGRAM
INPUT SIGNAL AND OUTPUT SIGNAL
Communicates the signal from each control unit via CAN communication.
| Control unit | Signal status |
|---|---|
| ECM | Transmits the following signal to EPS control unit via CAN communication:
|
| ABS actuator and electric unit (control unit) | Transmits the following signal to EPS control unit via CAN communication:
|
| Combination meter | Transmits the following signal to EPS control unit via CAN communication:
Receives the following signal from EPS control unit via CAN communication:
|
DESCRIPTION
- EPS control unit performs an arithmetical operation on data, such as steering wheel turning force (sensor signal) from the torque sensor, vehicle speed signal, etc. Then it generates an optimum assist torque signal to the EPS motor according to the driving condition.
- In case of an error in the electrical system, the fail-safe function stops output signals to the EPS motor. Refer to Fail-Safe .
- EPS control unit decreases the output signal to EPS motor during extreme use of the power steering function (e.g., full steering) for protection of the EPS motor and EPS control unit (Overload protection control).
- Extensive steering at low speed will cause the EPS control unit and EPS motor to heat up. Once temperature reaches the critical point, the EPS control unit will reduce current to reduce heat up. System will recover as temperature lowers (reduced or no assistance).
EPS WARNING LAMP INDICATION
- Turns ON when there is a malfunction in the EPS system. If ON, fail-safe mode is engaged and the system enters a manual steering state (turning force at steering wheel becomes heavy).
- Also turns ON when ignition switch is placed ON, for purpose of lamp check. Turns OFF after the engine starts, if system is normal.
| Condition | EPS warning lamp |
|---|---|
| Ignition switch ON. (Lamp check) | ON |
| Engine running. | OFF |
| EPS system malfunction [Other diagnostic item] | ON |
CAUTION:
EPS warning lamp also turns ON due to data reception error, CAN communication error etc.