Power Steering
Power Steering
The power steering system consists of the following components:
- Inner tie-rod ends
- Power steering pump (includes Fuel Efficient Power Steering (FEPS) solenoid/actuator)
- Power steering fluid reservoir
- Power steering fluid cooler
- Pressure and return lines/hoses
- Steering Effort Control Module (SECM)
- Rack-and-pinion steering gear
- Steering wheel rotation sensor
The FEPS system reduces vehicle fuel consumption by reducing the amount of power steering assist provided at higher engine speeds, when less assist is needed. The FEPS system is controlled by the SECM, FEPS solenoid/actuator and the steering wheel rotation sensor. As the steering wheel is turned, the steering wheel rotation sensor, which is mounted to the steering column, generates a steering wheel turning rate signal, which it sends to the SECM. The SECM also receives a vehicle speed signal from the ABS module. The SECM uses both of these signals to determine how much assist is needed. At slower speeds, full power steering assist is provided. As vehicle speed increases, the SECM sends a signal to the FEPS solenoid/actuator, which is mounted to the power steering pump. The FEPS solenoid/actuator is then activated to reduce the flow of power steering fluid through the power steering system. Power steering pump effort is reduced, which in turn, reduces the demands on the engine from the pump. With less load on the engine, the vehicle has greater fuel efficiency.
The power steering pump is a vane-type pump which is driven by the engine. A dedicated power steering pump belt connects the power steering pump and pulley to the engine. The power steering pump pulls power steering fluid from the power steering fluid reservoir, pressurizes it and pumps it through the power steering pressure line to the steering gear. From the steering gear, power steering fluid is returned to the reservoir through the power steering return line, power steering fluid cooler and power steering return hose.
For maximum power steering fluid cooling, the power steering cooler is mounted to the vehicle in front of the vehicle radiator and A/C condenser.
The outer tie-rod ends connect the steering gear to the wheel knuckles.