Air suspension (EAS)

The L322's Electronic Air Suspension (EAS) replaces steel springs with air springs at all four corners, giving a variable ride height and a famously smooth ride while retaining serious off-road articulation. It is one of the car's defining features, and, with age, its single most common source of faults.

Summary: The air suspension is brilliant when healthy and a known weak point when neglected. Most faults are well understood and fixable: diagnose before converting to coils.
AT A GLANCE Benefit: superb ride + adjustable height · Risk with age: the #1 L322 fault area · Golden rule: read live height data before replacing parts

Ride heights

SettingHeightUse
Access modeloweredDrops the car for easy entry/loading (at rest)
Standard172 mmNormal on-road ride height
Off-road227 mmRaised for rough terrain
ExtendedmaxHold the button for extra height when off-road isn't enough

If the car "bellies out" off-road, the control system senses reduced load on the air springs and automatically raises ride height to maximise articulation.

A clever feature that debuted on the L322 in 2002: the cross-linked?Cross-linking opens electronic valves connecting the air lines of diagonally/laterally adjacent springs. When one wheel lifts off-road, air pushes the opposite wheel down, mimicking the articulation of a live axle. air system. Electronic valves can connect adjacent air springs so that, when one wheel is lifted off-road, the opposite wheel is forced down. Recreating the articulation benefit of a traditional live axle while keeping independent suspension's on-road comfort.

How it works

  • An air compressor (under the rear, by the spare) feeds a reservoir and the four air springs.
  • A valve block directs air to each corner.
  • Height sensors at each wheel report ride height to the control module.
  • The module maintains level and adjusts height by driving mode and speed.
Control module (EAS ECU) Compressor + reservoir Valve block Air spring FL Air spring FR Air spring RL Air spring RR Height sensor at each corner reports back to the module air line sensor signal
How the parts connect: the compressor feeds the valve block, which sends air to each corner; height sensors feed back to the module, which keeps the car level.

Common faults

Most faults share one symptom: a "SUSPENSION INACTIVE" message, slow or no raising, being stuck in standard mode, or limp-home mode. The car is ~2.5-3 tonnes, so the system works hard. Typical causes:

CauseNotes
Air spring (bag) leakPerished bellows; a corner sags overnight. Most common cause.
Valve block leakInternal seals leak; system can't hold/build pressure.
Compressor wearWorn compressor can't build pressure; slow rise.
Height sensor faultFalse readings; uneven or failed levelling.
Exhaust valve stickingCan prevent lowering, or pump only one end.

Diagnosis & fixes

GOLDEN RULE No EAS component should be replaced on symptom alone. Read individual height-sensor live data first, many parts get changed needlessly. A proper diagnostic that reads EAS faults is essential; a cheap code reader is not enough.
  • Confirm whether the system is losing air (leak) or failing to build pressure (compressor/valve).
  • Listen for hissing at the bags and valve block; inspect the compressor.
  • Some owners convert to coil springs to escape recurring faults, at the cost of ride quality and height adjustment.
TIP A quick lock-to-lock steering turn, or raising/lowering the suspension a few times, can sometimes clear a basic "air suspension inactive" warning, but recurring faults need proper diagnosis.

Frequently asked questions

How does the L322 air suspension work?
An electric compressor feeds air to a spring at each corner, with height sensors and a control module keeping the car level and letting it raise or lower. It replaces conventional steel springs and gives variable ride height.

Why does the air suspension keep failing?
The usual causes are air leaks from perished springs or fittings, and a worn compressor that can no longer hold pressure. A fault often returns because the underlying leak was never found, only the warning was reset. See air suspension faults.

Should I convert to coil springs?
Some owners fit coil conversions to escape recurring air faults, but you lose ride quality and height adjustment, two of the things that make the L322 special. Most faults are fixable, so conversion is a last resort rather than a first move.

Can I drive with an air suspension fault?
Usually for a short distance at reduced speed, and the car often limits you automatically. Driving far with a corner sitting on its bump stop risks damage, so fix it rather than ignore it.

How do I diagnose an air suspension problem?
Read the individual height-sensor live data with a proper diagnostic tool before replacing anything. A cheap code reader is not enough, and parts get changed needlessly without proper data.