Steering control module
Electromechanical power steering (EPS)

Steering control module

  • Improvement in fuel economy of up to 0.8 l/100 km with electromechanical power steering
  • Maintenance-free and significant weight reductions
  • Flexible mounting positions allow use in all vehicle segments
  • Fail Operational Electronic for high availability and autonomous driving

HELLA has developed a steering control module for electromechanical power steering that enables demand-driven operation of the EPS, thereby increasing the vehicle’s fuel economy, and also develop Fail Operational Electronics to enable up to Level 4 autonomous driving.


  • Steering control module

The ever-stricter regulations for reducing CO2 emissions require fuel-efficient products. Moreover, autonomous driving requires reliable and precise steering systems. Since 2010, HELLA has been producing electronic control units (ECU) for Electrical Power Steering (EPS) to support and promote fuel efficiency as well as autonomous driving. They allow needs-based steering assistance by means of an electronically controlled electric motor: the steering control module (SCM) calculates the required steering support based on the incoming signals from the sensor system. The SCM also controls the EPS system’s electric motor power supply to deliver the appropriate level of assistance.

Control systems not only facilitate vehicle maneuvering and improve fuel efficiency, but also form the foundation for implementing various functions of automated driving, such as lane keeping assistance or automated parking. In addition, active safety systems are increasingly required to increase road safety. Therefore, HELLA continuously develops its Electronic Control Units and offers them in a Fail Operational version. This means that in the event of a fault in the electronics, the system will not be shut down, but the EPS will continue to work. With the Fail Operational function, HELLA has laid an important foundation for the ECU being suitable for SAE level 4 automated driving.

More than 25 million units of Hella SCM are already in the field, and over the coming years, HELLA will continue to enhance its capacity production by expanding its ECU global production capacities to strengthen its position as one of the 3 leading suppliers of EPS systems and Electronic Control Units in Europe. Currently produced in Germany and China, the company intends to also produce the units in Romania, Mexico, Brazil and India by 2020.

  • Easy adaption to requirements of different OEMs
  • ISO26262 ASIL-D compliant
  • Integrated AutoSAR 4.x Basic Software
  • Build-to-print service to Full-ECU design
  • Design-to-Cost
  • Fail Safe and Fail Operational Electronics

HELLA also supplies steering torque sensors, combined steering torque and angle sensors and motor position sensors based on CIPOS® technology.


Fail Safe electronics for safe driving

  • ISO26262 ASIL-D compliant
  • Partial automated driving possible
  • Drives motor to allow the required steering support based on the incoming signals from the steering sensor
  • Self-diagnoses internal circuits to allow ramp-down of assistance in case of failure
  • Operating from 7V up to 27V
  • Battery currents from 80A up to 120A RMS
  • Electronic architecture is based on a lock-step µC and includes all the needed HW safety mechanisms to fit for ASIL D EPS applications
  • Reverse battery protection and motor phase cut-off based on solid-state transistors
  • Basic software and complex drivers based on AutoSAR 4.x

EPS Fail Operational electronics ready for autonomous driving

  • ISO26262 ASIL-D compliant
  • Enables automated driving up to level 4
  • Modular design from 10 to 500 FIT, from semi to full redundant hardware architecture
  • Compliant with Hella Torque and Angle Sensor (TAS) Gen3 (2 measurement channels for both the steering wheel torque and the steering wheel absolute angle)
  • Operating from 7V up to 27V
  • Pic phase current up to 2 x 107A (for redundant designs) 3 phase motor: software degraded mode strategies to continue safe operations
  • 6 phase motor: independent second power stage to drive the remaining 3 phases in case of failure
  • Galvanic separation between two ECU paths (10 FIT)
  • Second battery interface added to reach level 4
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Electric Power Steering

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