In this article, we discuss the Land Rover LR3 Air suspension, the most common LR3 Air suspension issues and tips on how to troubleshoot these to encourage LR3 owners to DIY, save money and continue to enjoy these classic luxury vehicles.
What are the most common Land Rover LR3 Air suspension Problems?
- Suspension Fault Message
- Front/Rear Suspension Dropping Overnight
Land Rover LR3 Suspension
Four Corner Independent Air suspension was available from the LR3 (2004-2009) generation onwards. The air suspension was cross-linked to counteract Roll motion by balancing air pressure between opposite side air springs.
The LR3 generation Air suspension had the following architecture:
Land Rover Discovery LR3 Air Suspension Component Layout
- The Land Rover Air suspension is also called EAS (Electronic Air Suspension)
- The 4 corner suspensions are air struts which do the job of springs, but at the same time, also raise and lower the level of the vehicle, depending on the ride height selected by the driver.
- A compressor is connected to 2 Valve Blocks (one each in the front and rear) which supply air to the Air Struts at each wheel.
- The EAS system maintains the desired ride height by running the compressor to air into the air struts and by compensating for any level difference between the corners by either pressurizing or exhausting air from the individual Air Struts.
Discovery LR3 Air Suspension Components
- Front Right air spring damper module
- Front Right height sensor
- Air suspension control module
- Air suspension control switch
- Rear Right height sensor
- Rear Right air spring damper module
- Air supply unit silencer
- Rear Left air spring damper module
- Air intake filter
- Rear valve block
- Rear Left height sensor
- Upper acoustic cover
- Lower acoustic cover
- Air supply unit
- Reservoir valve block
- Air reservoir
- Front LH height sensor
- Front LH air spring damper module
- Front valve block
Suspension Fault Message
- After starting, the ‘Suspension Fault Normal Height Only’ message appears after approximately 30 secs
- Suspension Warning indicator lights up continuously
Possible Root Causes for Suspension Fault Normal Height message:
- Within the first 30 secs of start up the air suspension compressor works to pressurize the system and fill the reservoir
- Hence, the problem is related to the working of the compressor:
- The compressor not turning on at all
- The compressor working but in a faulty manner and unable to develop the required pressure
- The 2 main causes for Compressor malfunction are:
- Faulty Fuse/ Relay
- Worn out Air Compressor
Troubleshooting Suspension Fault Message: Air Compressor Fuse and Relay
- If there is no compressor working noise, then it could be an electrical issue
- The first thing to check would be the fuse and Relay to the Air suspension system
Troubleshooting Suspension Fault Message: Faulty Air Compressor
- Before physically removing the compressor, it would be good to read the Fault codes using a Diagnostic Tool
- If the Fault Code CA120 shows, it means a faulty compressor that is not able to develop enough pressure within a preset amount of time
- This points to either:
- A compressor with a clogged Desiccant, or
- A completely worn out compressor
- Before you remove the air compressor, as a safety precaution, it is advised to always disconnect the battery terminals. The reason being that the EAS always tries to compensate for any loss of pressure by either exhausting or running the compressor automatically. While working underneath the car, any change in suspension level could be dangerous.
Replacing the Air Compressor Desiccant
- The LR3 air compressor comes with a desiccant chamber through which all the input air passes so as to remove moisture.
- The desiccant beads are originally blue in color and become brown over time, finally becoming fully saturated and block the air passing through it.
- These desiccant beads can be replaced so that the original air flow rate of the compressor can be restored.
Replacing / Rebuilding the Air Compressor
- Although there are rebuild kits available for the LR3 compressor, replacement would be the most ideal solution.
- Rebuild kits would usually contain the Piston rings, Retainer Springs and O-rings required to restore the compressor’s capability to seal air.
Front/rear Suspension Dropping Overnight
- After long hours of parking or overnight parking, the suspension height drops at either the front two wheels or all4 wheels
- Vehicle, once started, is able to lift the suspension to ‘Off-Road Height’
- Suspension warning light continuous in the Dashboard
- Loud Compressor Noise due overworking
Troubleshooting Front/Rear Suspension Dropping Overnight: Air Leakage
- Check and confirm the height of the wheel center from the bottom of the fender before and after parking on each side
- To check whether the issue is due to a leak, one way, is to
- Raise the height to maximum or Off-Road
- Remove the air compressor fuse and leave the vehicle parked overnight
- This is done to disable the height adjustment mechanism that provides air to the strut from the reservoir
- If, after disconnection, overnight parking causes a drop in suspension height, then it is most probably due to a leak within the air circuit
- Leakage test can also be done by spraying soapy water solution over the air struts, air lines, valve blocks and all air connections. Look for bubbles that froth and stay at one spot even after wiping them with a finger.
- As a Caution, if any leakage problem in the air suspension is ignored the compressor will need to work extra in order to compensate for any loss of pressure in the system. With such overloads, the compressor could eventually wear out prematurely and seize.
- In most Land Rovers, the most vulnerable position for air leaks would be the air struts.
Troubleshooting Suspension Dropping Overnight: Air Spring Damage/Wear Out
- Air Spring Damage is a common problem with Land Rovers.
- The Air Springs tend to wear out at the top and bottom over time, or they can blow out suddenly when damaged by road debris.
- Slow leaks in air springs can overwork the air compressor pump.
- The Air Springs usually have a life of 100,000 miles or 6 years in most climates.
Troubleshooting Front/Rear Suspension Dropping Overnight: Valve block Failure
- If either both the front or both the rear struts have dropped, then there is a chance that these struts were not supplied air. The Front/Rear Valve blocks are responsible for this supply.
- Over time, the Valve Blocks could eventually start leaking or could fail to shut off air flow between the individual air struts. A Valve Block malfunction could have been the reason why the front/rear air struts were not getting filled.
- Valve Block Leakage can be easily detected by spraying soapy water solution
- Even if there is no leakage, the Valve block could still be damaged
- The front Valve Block is on the Right Chassis Rail right behind the Front bumper
Troubleshooting Front/Rear Suspension Dropping Overnight: Faulty Ride Height Sensors
- The air suspension sensors in the Land Rover get damaged from harsh weather, dirt or Road Debris.
- Any kind of sensor malfunction or failure will make the vehicle incapable of leveling itself.
- In addition, the vehicle could get stuck at one particular ride height setting.
In this brief article, we have discussed the Land Rover LR3 Air suspension, the most common LR3 Air suspension issues and tips on how to troubleshoot these to encourage LR3 owners to DIY, save money and continue to enjoy these classic luxury vehicles.