System Operation
The EPS control unit controls the EPS motor by these signals:
- Vehicle speed signal (from PCM)
- Engine speed signal (from PCM)
- Torque sensor signal
At idle or low vehicle speeds, the EPS control unit sends a signal to the PCM to increase the engine idle speed to prevent the engine from stalling.
When the EPS control unit detects a failure in the system, it stores a DTC and sends a signal to the gauge control module to turn the EPS indicator on.