Electronic Air Suspension

From Wikipedia, the free encyclopedia

Electronic Air Suspension is the name of the air suspension system installed on the second version of the Range Rover, known as the P38A.

Overview

The EAS provides variable height suspension for on and off road applications. The five suspension heights offered by EAS are (from lowest to highest in terms of height) "Loading," "Highway," "Standard," "Off-Road," and "Off-Road Extended." Height is controlled automatically based on speed and undercarriage sensors, but a manual ride height switch allows control over the suspension by the driver. The "Loading" and "Off-Road" heights are available only at speeds less than 35 mph. The "Highway" setting is not available manually; it is set when the vehicle moves at over 50 mph for over 30 seconds.

Components

The system comprises:

  • a vulcanised rubber air spring at each wheel
  • an air compressor, located under the bonnet
  • a compressed air storage tank, storing air at ~150psi (1000 kPa)
  • a valve block which routes air from the storage tank to the four air springs via a series of solenoids, valves and many o-rings
  • an EAS computer which communicates with the car's main computer the BeCM and decides where to route air pressure
  • a series of 6 mm air pipe which channels air throughout the system (mainly from the storage tank to the air springs via the valve block)
  • an air drier canister containing desiccant

Advantages

The air springs were designed to provide a luxurious ride quality and provide the ability to raise the body of the vehicle for off road clearance and lower the vehicle when driving at higher speeds on highways.

Problems

The EAS computer is regarded by some to be unintelligent. It can, using pre-programmed criteria to detect a fault, disable the system into "Hard Fault Mode" which can lower the vehicle to the suspension bump-stops and force the owner to limp to the dealership for inspection and repair.

Many enthusiasts use diagnostic devices such as laptop computers running specially developed freeware software and hand held computers to clear the spurious faults and avoid the trip to the dealer. Some even manipulate the sensors and set the vehicle to the maximum possible ride height at all times.

This article is issued from Wikipedia. The text is available under the Creative Commons Attribution/Share Alike; additional terms may apply for the media files.