2003 BMW X5 sensor

HOOD CONTACT SWITCH
Located on the right side engine com-
partment, the hood contact switch pro-
vides a ground signal to the GM signifying
an open hood.
The plunger of this switch can be pulled
up past a detent causing the switch con-
tact to open. This feature can be used to
simulate a closed hood with the hood
open when diagnosing the DWA system.
DWA LED
The LED is provided with constant battery voltage (KL 30). The GM provides a switched
ground signal providing the various blinking signals used to convey DWA status to the vehi-
cle operator (covered further on).HOOD SWITCH
COMPONENTS
DOOR CONTACTS
As mentioned in the Central Locking Section, the door lock contact hall effect sensors pro-
vide status of door open/closed. The GM will activate the siren if a door open signal
becomes active when the DWA is armed.
TAILGATE SWITCH CONTACTS
The tailgate switch contact is located in the tailgate lock actuator assembly. When closed,
the tailgate contact provides a ground signal to the GM signifying a "closed tailgate". The
GM will activate the siren if the tailgate switch contact ground signal opens when the DWA
is armed.
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TILT SENSOR
Located in the electrical carrier forward of the glove
box, the tilt sensor is an electronic sensing device with
the sole purpose of monitoring the vehicle's parked
angle when DWA is armed.
The sensor requires three signal wires to perform its function:
• KL 30 - Constant battery voltage
• Signal "STDWA"; switched ground input signal provided by the GM indicating DWA
armed/disarmed status. The tilt sensor is used as a splice location for the STDWA sig-
nal to the Siren and FIS interior protection sensor.
• Signal "NG"; switched ground output signal provided to the GM. The signal is used for
two purposes,
1. As a momentary acknowledgment that the tilt sensor received STDWA and is cur-
rently monitoring the vehicle angle.
2. If the tilt sensor detects a change in the vehicle's angle when DWA is armed, signal
NG is switched to inform the GM to activate the siren.
When the tilt sensor receives the STDWA signal from the GM it memorizes the vehicle's
parked angle. The angle of the vehicle is monitored by the solid state electronics. Once
armed, if the angle changes, the tilt sensor provides a switched ground signal to the GM to
activate DWA.

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INTERIOR PROTECTION (UIS)
The UIS monitors the vehicle interior for motion through ultrasonic sound waves. The UIS
is a combined transmitter and receiver.
The X5 UIS sensor is incorporated into the
rear seat interior light trim cover. It is a two
piece unit with cable connection to the rear
transmitter/receiver.
The UIS and trim panel are clearly identified
with arrows indicating forward mounting
direction.
Due to the design of the vehicles interior,
the sensor is uni-directional and must be
installed in the proper direction to ensure
proper operation of the system (trim cover
ensures directional installation).
Every time the DWA system is armed (signal STDWA), the sensor adapts to what ever
objects might be stationary in the interior.
The sensor emits ultra sonic waves in a pro-
grammed timed cycle. It receives echos of
the emitted waves.
The UIS amplifies the received sound wave
signals and compares them with the trans-
mitted waves. The UIS also checks the
incoming echos for background hiss (wind
noise through a partially open window) and
adapts for this.
• If the echos are consistently similar, no movement is detected,
• If the echos are altered, (inconsistent), the UIS determines motion in the interior com-
partment.
If motion is detected, the UIS changes to a constant cycle and the echo is compared again.
If the inconsistency is still present the UIS sends the activate siren signal (INRS) to the GM.
As with the tilt sensor, the UIS is also switched OFF when the vehicle is locked two times
within ten seconds. This allows the sensor to be switched OFF for transportation purpos-
es.

ALARM SIREN
The siren is located in the vehicle cowl
on the driver’s side of the vehicle. This
location provides a secure position with
loud acoustic output.
The siren contains electronic circuitry
for producing the warning tone when
the alarm is triggered. The siren also
contains a rechargeable battery that is
used to power the siren when the alarm
is triggered.
The rechargeable battery will allow the siren to sound if it or the
vehicle’s battery is dis-connected. The siren battery is recharged,
from the vehicle’s battery when DWA is not in the armed state.
The siren has four wires connecting it to the system; KL 30, KL 31,
Signal STDWA (arm/disarm signal from GM), and Signal NG (acti-
vate siren output signal to the GM)
The arm/disarm output signal from the GM (STDWA) is provided to the Tilt sensor, FIS sen-
sor and the siren simultaneously. The arm/disarm signal is a switched ground that signals
the components of DWA armed/disarmed status.
The activate siren signal (NG) is high whether DWA is armed or disarmed. If a monitored
input activates the alarm, the high signal to the siren is switched to a 50% duty cycle at
the GM. The control circuitry in the siren activates the siren driver. If the DWA is armed
and the battery is disconnected the siren recognizes the normally high “NG” signal as sud-
denly going low, the siren is also activated.
SIREN INSTALLATION
POSITION
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DWA ARMING/DISARMING
• The DWA is armed every time the vehicle is locked from the outside with the door lock
cylinder or FZV key.
• The LED in the rear view mirror flashes as an acknowledgment along with the exterior
lights and a momentary chirp from the siren.
• The GM monitors all required input signals for closed status (door closed, tailgate
closed, etc.) The inputs must be in a closed status for a minimum of 3 seconds for the
GM to include them as an activation component. If after 3 seconds any input signal not
in the closed status is excluded (this is acknowledged by the DWA LED) preventing false
alarm activation's.
• If the DWA is armed a second time within 10 seconds, the tilt sensor and interior pro-
tection sensor are also excluded as alarm activation components. This function is use-
ful if the vehicle is transported on a train or flat bed truck to prevent false alarm activa-
tion's.
• While armed the tailgate can be opened with out the alarm being triggered as follows:
- If opened with the tailgate remote button via the FZV, the GM prevents the alarm
from activating. (This feature is customizable under the Car Memory function).
- If opened with the key at the tailgate lock cylinder the tailgate key position switch
signals the GM and in the same manner prevents the alarm from activating.
In either case, when the tailgate is returned to the closed position, it is no longer con-
sidered as an activation signal.
Panic Mode Operation: When the tailgate button is pressed and held, the GM is signaled
to activate the siren for the Panic Mode. The panic mode will function with either an armed
or disarmed DWA system.
EMERGENCY DISARMING
Emergency disarming occurs automatically if a key is used to turn the ignition switch on and
the EWS III accepts it. The EWS III signals the GM to unlock the doors and deactivate the
DWA.

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SLEEP MODE
To lower the constant battery draw when the vehicle is parked, The complete ZKE system
will go into the “Sleep Mode” 16 minutes after the ignition has been switched off and no
further ZKE function is active.
Approximate X5 Battery draw: • Ignition switch off = approx 750 mA.
• One minute after = approx. 560 mA.
• After 16 minutes (sleep mode) = approx. 18 mA.
All modules in the ZKE system will go into the sleep mode. The P-Bus remains active, how-
ever no data transfer takes place until a wake-up request is received. The general module,
door modules or keyless remote module can wake the system up and put the ZKE back
on line. The K-Bus is not active in the sleep mode, however the GM III of Remote Entry
Module can put the K-Bus back on-line with a wake-up request.
SLEEP MODE CRITERIA: KL R, 15 OFF and no further function activated for 16 minutes.
WAKE UP CRITERIA: KL R or 15 “ON” or a change in one of the signal states listed below.
SIGNAL ACTIVITY ORIGINATING
MODULE
K-BUS High General Module
Door jamb switches (possibility of 4) Low “
Trunk lid lock cylinder microswitch High “
Trunk lid pushbutton microswitch Low “
Interior Trunk lid pushbutton microswitch Low “
Central locking button Low “
Hood microswitch Low “
Trunk Lid microswitch Low “
Interior light switch Low “
FIS sensor Low “
Tilt Alarm sensor Low “
FBZV operational signal High FBZV Module
Driver’s door lock microswitch - (lock) High PM-FT/SB
““““ - (unlock) High “
Passenger door lock microswitch - (lock) High PM-BT
““““ - (unlock) High “
Tailgate
Tailgate
Tailgate
Tailgate
UIS