Rear air suspension

why does my 2006 cls500 have light car too low

The air system does not lower when you get out, it levels the car and stays level, but is you put weight in trunk and people sitting in the back seat and the car lifts to level out with the weight and then you remove all the weight and rear end is to high up then there is a problem.
These bags do not lift that high, if you hear the solenoids make sure it is not lower , measure.Also, the release of the air is very slow, make sure it is not lower, if you hear the solenoids open the car may be lowering very slow. check the height.If you are sure its not lowering then you may be correct in saying the level sensor may be bad. the only other part would be the solenoids but i would start with the level sensor as the air is going into the bags.
I quick test to check solenoids at bags is to start car and go rear the rear and locate the sensor, remove the arm from the control arm and bring it down so computer thinks car is to high and see if air is released. caution don"t stay under the car as it will lower down slowly. if it starts to lower then turn key off and reconnect lever and replace sensor.there is a company we use that is real good at this air bag system and prices are good with quality parts.http://www.arnottindustries.com/part_LINCOLN_Air_Suspension_Parts_yid2.html

Hi Jose:
The first place to start is to have Ride Control Module scanned for trouble codes, this requires a high end scan tool. Most common problem is the air compressor in the rear or a height sensor. Here is how the system works.

Automatic Level Control Description and Operation
The RTD system is bi-state real time damping system. The Suspension Control module controls the suspension damper solenoids and suspension position sensors, along with parts of the automatic level control (ALC) system and electronic variable orifice (EVO) power steering system.

The Automatic Level Control system consists of the following:
• Suspension Control Module
• Compressor/Leveling Module
- Air Pressure Sensor
- Exhaust Solenoid
• Compressor Motor Relay

The objective of the Automatic Level Control System is to provide constant ride height at all load conditions. The Suspension Control module monitors body-to-wheel height, and vehicle speed.

The Suspension Control module will use the rear body-to-wheel displacements and vehicle speed inputs to keep the rear trim height of the vehicle at its desired level.

The electronic suspension control (ESC) system is bi-state real time damping system. The ESC module controls the suspension damper solenoids and suspension position sensors, along with parts of the automatic level control (ALC) system, if 1500 series.

The ESC system consists of the following:
• The ESC module
• The compressor/leveling module, if 1500 series
- The air pressure sensor, if 1500 series
- The exhaust solenoid, if 1500 series
• The compressor motor relay, if 1500 series
• The steering handwheel speed/position sensor
• The suspension damper solenoids
• The suspension position sensors

Hope this helps; also keep in mind that your feedback is important and I'll appreciate your time and consideration if you leave some testimonial comment about this answer.

Thank you for using Fixya, and have a nice day.

Most likely you have struts on the front and air bags on the back.
To fix a sagging rear end, it will cost more than the value of the car.
There is a Canadian company named strutmasters, google it, which sells kits to convert self leveling air bag suspensions to real ones with shocks and springs.

there are 2 ways of fixing that problem you can replace whats broken which is more than likely the air bags, which is expensive, or you can get an aftermarket set up with regular springs and do away with the air bag system completely it's not hard to convert it over just unplug the compressor jack up the car to lift the weight off of the suspension put a jack under the rear end housing and loosen the the shocks and lower the rearend housing remove the air bags put springs in their place jack up the rear end bolt shocks back up and your done.

Air suspension needs compressed air for the control of Air Springs (Air Spring is a cylinder like thing which goes up and down when air is pumped in and out of it). For pumping in and out the air, air compressor needs to be switched ON/OFF. Compressor relay connects and disconnects the compressor motor from the power supply ( battery). ----------------- air ride suspension compressor located under the air filter box . ---------------- the Air compressor clutch relay location
is fitted to the left hand inner wing (when viewed from the the driving seat).
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the compresser is located on the left hand side of the car under the hood.
once you open the hood remove the air cleaner housing and windshield washer resivor.
there is a panel that you lift up under both of thoese that is where the compresser is located
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1. The air suspension uses a small, separate air compressor under the driver's side left fenderwell, with air lines running to the air bags. On the top of each air bag is a electrical valve. This is a relief valve that allows air to be exhausted when activated, and which senses the amount of air pressure within the air bag to keep both sides equal. These valves are operated via a leveling sensor that is attached to the body of the car and to the rear axle by a movable arm. When the rear of the car drops due to increased load, the arm is pushed up. When the arm is pushed up, it turns on the air compressor and fills the air bags to level the car. When the load is removed and the arm moves down, indicating that the back of the car has risen, the sensor opens the valve on the air bags and allows air to escape, lowering the car.
2. If the back of the car is low, indicating that the air suspension is not working, and the air suspension light is on, check the fuse first. If the fuse is all right, check the air suspension switch in the trunk and make sure it is on. This switch is used when the car is in for service. Always turn off the switch before lifting the car, because the sensor will think the car is rising and keep the air bag valves open, ruining the rear air suspension.
3. Turn the ignition key with the engine off. Listen for the compressor to come on while pushing down on the rear bumper. If it does not come on, test the switch terminals for power, using a circuit tester. If one terminal has power and the other does not, replace the switch. If there is power, turn the switch to the off position, raise the vehicle and place it on jack stands in the rear. Inspect the leveling switch on the axle, making sure it is not bent and is connected. Use an ohmmeter for this test. Pull the electrical connector off the switch. Loosen the arm of the switch from the axle. Test the switch with the ohmmeter by checking across both terminals while slowly moving the arm. There should be no continuity with the arm down. As the arm is raised, there should be continuity. If not, replace the switch. If there was continuity, connect the arm and the electrical connector.
4. Put a floor jack under the axle and raise the axle to the point where it is just beginning to lift the car off the jack stand. Turn on the ignition. Turn the air suspension switch to the "on" position. Use the circuit tester to check for power at the leveling switch. If there is power, turn the air suspension switch to "off" and lower the car. Access the air compressor in the front, under the hood, and check the electrical connector for power. If there is power, check for a good ground. If both are good, replace the compressor. If the compressor works and the car does not rise in the back, replace the air bags.

you need rebuilt or new air struts.their easy to change but you should have a lift it makes it very easy.

IFYOU FIND THE AIR BAGS ARE LEAKING (USUALLY IS THE PROBLEM) JUST REPLACE IT. LIFT UP THE REAR REMOVE THE TIRE ,DISCONNECT THE PLASTIC LINE THAT GOES TO THE AIR BAG (push the little grommet pull the plastic hose) DISCONNECT THE WIRE CONNECTOR, AND REMOVE THE CLIP AT THE TOP OF THE AIR BAG (JUST PULL IT) AND REMOVE THE AIR BAG (REVERSE TO INSTALL IT)
(YOU CAN REMOVE THE AIR BAG IN ABOUT 40 MINUTES) EACH SIDE.( on ebay you can find replacement to a regular shocks) or air bags

rear suspension ride leveler mslfunction. Check Air compressor function.

did you replace the leveling arm in the same position as before?