2001 BMW 540i Antenna

The Remote Entry System incorporated minor changes since the original introduction
which includes:
• The control electronics are incorporated into the GM III.
• The antenna is incorporated into the rear window lower heater grid.
• The remote key receiver is installed in the left “C” pillar. The receiver produces a digital
signal based on the transmitter command and sends it to the GM for processing. The GM
then carries out all remote entry operations either directly or through the door modules
for the front doors. The frequency at which the key transmits the radio signal to the ant-
enna amplifier is 315 MHz.
Vehicle/Key Memory
The Vehicle/Key Memory feature provides the flexibility of allowing the owner to customize
certain functions of select vehicle systems and automatically identifies users of the vehicle
by a key identification signal provided by the remote keyless entry system (FZV).
Vehicle & Key memory is marketed as a combined feature but is actually two separate func-
tions of the select vehicle control systems.
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Central Body Electronics ZKE III
A
IHKA
K-BUSKEY #1
KEY #2
KEY #3
KEY #4
GMV
SM
Adjust Setting of Seat
For Key #1 IHKA Features Key #1
Being Used
KEY 4
KEY 3
KEY 2
KEY 1
KEY 1
- Selective Unlocking
- Automatic Locking
615200099.eps

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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Central Body Electronics ZKE III
615200049.eps 615200100.eps

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