Level control system, basic function

GF32.33-P-1002A

Level control system, basic function

22.06.2020

Model

all (CAR)

Overview

This document contains information on:

 General

 Function requirements

 Function

General

The level control system controls the air suspension individually at each wheel. Under normal operating conditions, the air suspension operates with different pressures depending on the load. The vehicle level is reduced or increased depending on the selected drive program. In addition, the vehicle level can be changed by the driver by pressing the appropriate button.

Function requirements

 Engine in operation

Function

Detection of vehicle level

The vehicle level is detected for each individual wheel by the following sensors:

 Left front level sensor

 Right front level sensor

 Left rear level sensor

 Right rear level sensor

Adjust vehicle level

To raise the vehicle level at the relevant wheel, the air pressure in the respective single-chamber air spring is increased.

To lower the vehicle level at the relevant wheel, air is released from the respective single-chamber air spring.

The single-chamber air springs are supplied with compressed air by the following sources:

 Air suspension system central compressed-air reservoir

 Air suspension system compressor, when the pressure in the central reservoir is not sufficient

To protect the compressed-air system against overloading, the air suspension control unit monitors the operating time of the air suspension compressor. The air suspension compressor is switched off for cooling when the maximum operating time is reached.

Increasing vehicle level

 Air suspension compressor ON (when the pressure in the central reservoir is not sufficient)

 Air suspension central reservoir filling valve open

 Corresponding level control valve open

 Air suspension pressure relief valve closed

Reduce vehicle level

 Air suspension compressor OFF

 Air suspension central reservoir filling valve closed

 Corresponding level control valve open

 Air suspension pressure relief valve open

	Additional base function
	Level control on rear axle, basic function	Model 213.2 as of model year 2021	GF32.32-P-9900A
	Detailed information
	Level control system, detailed information	Model 167 with code 430 (On & off-road package) Model 167 with code 489 (AIRMATIC) Model 167 with code 490 (Electrohydraulic suspension)	GF32.33-P-1100A
	Components
	Level sensor, basic function	Model all (CAR)	GF32.31-P-2001A