Specifications

Chassis Specialist : Electric Power Steering
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One of the benefits of EPS is an increase in fuel economy, according to Ford this increase can be up to
one mile per gallon. On a conventional power steering system, the pump will always be operating
whenever the engine is running. With the EPS system there is no parasitic draw on the engine. The
electrical power the system uses is readily available and draws on the system only when required.
Other benefits of the EPS systems are there are no hydraulic lines and less fluid, also, the rack and
pinion is smaller and lighter.
ELECTRIC POWER STEERING SYSTEM COMPONENTS
While the systems might be configured differently the operation and principles are the same. The EPS
is designed to reduce the effort needed to steer the vehicle. The systems consist of the steering rack and
pinion, a steering wheel position and/or steering torque sensor(s), a power steering control module
(PSCM) and the electric motor. The PSCM will monitor the vehicle speed signal via the controller area
network (CAN) to adjust the assist level provided.
Steering Rack and Pinion Assembly
The rack and pinion assembly on an EPS equipped vehicle is smaller and lighter. The rack and pinion
does not have an internal spool valve to control the hydraulic assist. The assembly does contain oil but
the oil is used for lubrication only, there is no hydraulic pressure in the system.