sport mode BMW X5 1999 E53 Workshop Manual
[x] Cancel search | Manufacturer: BMW, Model Year: 1999, Model line: X5, Model: BMW X5 1999 E53Pages: 52, PDF Size: 3.07 MB
Page 37 of 52
Air Springs
The air spring is made from a flexible rubber material. It
forms an air tight cavity which provides the calculated spring
rate required for the sport wagon.
As the spring compresses downward the bottom edge of
the rubber material rolls along the vertical surface of the
base mount cylinder.
Air is added or removed from the air spring through its top
port. The top port of each spring is connected to a reser-
voir and the air supply pipes. The reservoirs are required to
hold additional air due to the compact design of the springs.
Rear Axle Level Sensors
Hall effect sensors are mounted on the left
and right sides of the rear suspension for ride
height detection. They are pivoted by a cou-
pling rod through the rear axle swing arms.
The hall sensors produce a varying voltage
input to the control module as the suspension
height changes.
If the vehicle is equipped with Xenon head-
lights the right side sensor contains an addi-
tional sensor for the automatic headlight level
adjustment system.
Warning Display
If the system is faulted and off-line or set in the transport mode, the following is displayed:
High Cluster: A message is posted in the high cluster matrix display.
E39 Features 07
37
Page 41 of 52
41
EHC System Operation
A fully functional EHC system is controlled by one of three different modes of operation.
The operation mode is selected by the control module based on current conditions provid-
ed by the monitored input signals. The main modes of operation are:
• Pre-Run/Post-Run Mode
Normal Mode
Tailgate Mode
Two special operating modes are also included in the control module programming.
New/replacement mode(pre ZCS encoded). This mode provides basic operation.
Transport Mode - Transport mode is set at the factory and raises the vehicle 30mm to
prevent vehicle damage during transportation. It must be deactivated with the DIS/
MoDiC prior to customer delivery.
Pre-Run/Post-Run Mode
The Pre-Run mode is activated when the vehicle is parked and the control module is in the
sleep mode. Opening a door or the tailgate initiates a system wake up and the control mod-
ule comes on-line.
The control module performs a self-check of the control electronics and sensors. If no fault
is found, the system will check the ride height and institute a rapid regulation if the height
varies by more than 40mm.
Page 45 of 52
45
DIS/Modic Service Funnction Program
The Service Functions program of the DIS/MoDiC provides the Transport Mode activa-
tion/deactivation and Ride Height Offset functions (see next page).
Once the transport mode has been released, or if the system requires left to right side
height adjustment, the ride height "OFFSET" must be carried out to ensure that the vehi-
cles suspension has a base ride height level starting point.
The "HEIGHT OFFSET" is adjusted using the DIS or MoDiC. The procedure is as follows:
• Place the vehicle on a level surface unloaded.
• Access the Height Offset program in the service function menu.
• Measure the base ride height from the lower edge of the wheel housing to the center of
the wheel hub.
• Check measured height against the specifications listed
• Use the DIS/MoDiC to correct the ride height if the value differs from the listed specifi-
cation.