1994 BMW 750IL battery

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Central Body Electronics ZKE III
Power Distribution
The power distribution box for the
E38 is incorporated in the Electr-
onics box in the engine compart-
ment.
The power distribution box for the
E39 and E53 is inside the vehicle.
The main fuse box is located
inside the glove box above a
hinged panel.
A “pull out” fuse designation card
is also located in the fusebox. This
notes:
• Fuse value in amps
• Location
• Circuit listing by fuse
The placement of the power distribution box is
close to the main electronics carrier behind
the glove box. The modules/relays located in
the electronics carrier include (examples):
• General Module III (GM III)
• Drive away protection (EWS II)
• Anti-lock Brake (ABS/ASC+T)
• Light Check Module (LCM) - behind right kick
panel
• Overload protection relay module
An auxiliary fuse block is located in the trunk
above the battery. In addition to fuses, the
auxiliary fuse block also contains relays (exam-
ples):
• Fuel filler flap lock motor relay
• Fuel pump relay (some vehicles)
• Rear defroster relay
• Unloader relay
FUSE
DESIGNATION
CARDFUSE BOX DROPS
DOWN AFTER TURNING
TWO THUMB SCREWS
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Fused Power Distribution Centers
The E38, E39 and E53 utilize high amperage fused power distribution centers.
The E38 and E39 locations are found under the carpet on the passenger’s side floor and
in the right rear area of the trunk, forward of the battery.
The X5 utilizes a single high amperage fused
power distribution center located next to the
left side EHC air reservoir beneath the cargo
area floor paneling.
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Workshop Hints
Windshield Wiper Blade Service
To access the wiper blades for cleaning or replacement,the following is required:
• With the ignition switched on (KL15), switch the wiper stalk to the “Intermittant” wipe
mode.
• Switch the ignition off when the wiper arms are in the “upright” position.
CAUTION: Do not allow the wiper arm to spring back against the windshield, glass
breakage will occur!
Rain Sensor Equipped Vehicles
Make sure the wiper blades are in perfect condition. Only use window cleaner to clean the
windows. Dirty windows can cause the Rain Sensor control module to set a fault
due to the end limits of its adaptation abilities.
Rear Window/Wiper
The wiper arm and driveshaft are connected by
splines.
Special tool #61 1 320 is required to hold the drive
shaft in the park position prior to installing the wiper
arm on to the drive shaft.
Windshield Wiper System Diagnosis
The GM monitors the following circuits:
• Wiper Potentiometer • Wiper Motor • Terminal 30
• Double Relay • Windshield Washer Pump
Note: The wiper/washer operation will be interrupted during engine cranking. The GM pro-
vides this “unload” feature to preserve the battery voltage for the starter motor.
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Central Body Electronics ZKE III
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Remote (Keyless) Entry FZV
Purpose of the System
The Remote Entry System offers the following:
• Locking/unlocking of doors, luggage compartment (tailgate), fuel filler lid.
• Selective unlocking of driver’s door (same as with key in the lock cylinder).
• Arming/disarming of DWA alarm system.
• Remote unlocking of the trunk (tailgate) only.
• Comfort opening of windows and sunroof.
• Interior lighting activation (search mode).
• Panic mode alarm activation.
• Changing code signals - coded signals from transmitter change with every operation.
• Automatic correction for up to 1000 erroneous activation signals.
• Transmitter initialization procedure - including up to four key operation and Key Memory.
• Replacement batteries.
• Low transmitter battery in vehicles equipped with Check Control.
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System Components
Remote Key: Features:
• 3 volt lithium battery (commercially available CR 2016)
is used as the power supply for the key transmitters.
• An EEPROM is used to store the key data.
The data is not lost when the battery is re-
placed and initialization is not required.
• The key incorporates an LED that signals the opera-
tor of signal transmitting, key initialization status and
key self test indication.
• The keys are delivered
with a four color label
sheet containing differ-
ent colored labels for
each of the four pos-
sible FZV keys.
This is helpful to differenti-
ate the FZV keys during initialization preventing the pos
sibility of mis-assigning the key ID which would change
the encoded Key Memory functions.
Model Year 2000 Key
Visual Changes:
• New appearance with blue and white BMW roundel.
• New button arrangement (larger buttons) with seq-
uential operation (enhanced operating convenience).
Functions the same as the previous key.
• Rechargeable battery replaces replaceable batteries.
Charged by EWS ring antenna.
• The key housing is encapsulated and can not be
opened.
• The LED has been omitted.
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LED Status (Keys equipped with LED):
The following functions can be checked with the LED:
• Flashing LED when pressing a button.
Indicates that the data is being transmitted.
(battery voltage between 3.2 - 2.6 volts)
• No LED activity when pressing a button:
1. ZKE responds to pressed button only to
unlock a locked vehicle. Indicates the bat-
tery is between 2.6 - 2.2 volts. Replace bat-
tery.
2. No unlock of vehicle. Indicates battery is
below 2.2 volts. Replace battery.
FZV Key Test: Pressing the trunk release and lock buttons together activates the key test. If
the battery and FZV key EEPROM are “OK”, the LED will come ON for approximately 1 sec-
ond.
FZV Key Rechargeable Battery
From KL R, the battery inside the key head is charged inductively by the EWS ring antenna
via a coil antenna integrated in the key. The charging process is controlled by electronic
circuitry integrated in the key.
• The service life of a radio-control key used under normal conditions corresponds to the veh-
icle lifespan.
• If the FZV keys are not used (ie: stored in a drawer), the battery will be discharged after
approx. 1.5 years.
• The time required to fully charge a discharged battery is approx. 30 hours.
• The remote control can be operated about 15 times after a charging period of approx. 30
minutes (driving time).
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Central Body Electronics ZKE III

The key data is stored in a transponder chip. The transponder chip is a wireless read and
write EEPROM. It is powered via the ring coil at the steering lock. Power is applied elec-
tromagnetically when the key is in the ignition switch from KL R.
The power supply is used both for data transfer as well as for charging the battery. This has
been made possible by new development of the transponder chip.
As with previous systems, every press of an FZV key also provides the battery charge con-
dition. When the FZV electronics receives a low power condition message three successive
times, the GM sets a fault indicating a low battery within a specific key. The LCM is also
informed via the bus system and alerts the driver via an instrument cluster matrix message.
If the battery is recharged (used operate car), the fault will be automatically deleted when
five successive messages are received indicating a charged battery condition.
The battery has no affect on the EWS III communication function!
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Central Body Electronics ZKE III

Tilt Sensor (Liquid Type - E38/E39 to 97 MY): The Tilt Sensor consists of a conductive
liquid chamber, a processor board and metal probes (located in the luggage compartment).
The probes are submersed in the liquid and produce a resistance value dependent on the
tilt of the sensor (angle of vehicle). This resistance value becomes the static point when the
DWA System is armed.
If the vehicle is jacked-up or lifted,
the angle of the liquid changes
producing a change in the resis-
tance value. The sensor recog-
nizes this change and signals the
GM to activate the DWA alarm.
The resets at the new angle. This
allows the DWA to remain armed
and re-activate the alarm if the
vehicle is moved again.
As with the interior sensor, the tilt sensor is also switched OFF when the vehicle is locked
two times within ten seconds. The LED will flash one time for confirmation. This allows the
sensor to be switched OFF for transportation purposes.
Tilt Sensor (Electronic Type from 98 MY): Located in the luggage comparment area,
the tilt sensor is an electronic sensing device with the sole purpose of monitoring the vehi-
cle's parked angle when DWA is armed.
The sensor requires three signal wires to func-
tion:
• KL 30 - Constant battery voltage
• Signal "STDWA"; switched ground input sig-
nal provided by the GM indicating DWA
armed/disarmed status.
The tilt sensor is used as a splice location for
the STDWA signal to the Siren and UIS int-
erior protection sensor.
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