This document describes the requirements and operation of the Passive Entry System. However, this
document is especially for the Entry system ECU (acronym for Electric Control Unit) and the FOB.
The FOB consists the following functionality for passive access and active access:
•
Door unlocking / locking (however, only for request by means of switch operation)
•
LF decoding
•
RF encoding
•
Communication data encryption (cryptograph, anti-collision, rolling code and stuff)
And the entry system ECU consists of the following functionality:
•
Door unlocking / locking
•
Engine start (/ stop)
•
LF encoding
•
RF encoding
•
Communication data encryption (cryptograph, anti-collision, rolling code and stuff)
•
LF antenna unit control
•
Communication with the node ECUs connected to the body bus (e.g. CAN, J1850, customer
dependent bus)
As a further function, both the FOB and the entry system ECU provides the following function:
•
Learning mode for programming the manufacturing data and stuff
•
Data locking and password protection
•
Diagnostic (based upon ISO9141 if required)
Page 3
2.Passsive Accsess Entry Functionality
A handle sw located on, for example the door handles, mirrors will be used for proximity check if user is in
neighborhood of the vehicle. The switch input will trigger for unlocking and open the doors.
Door Handle SW
Figure 1
2.1.Door Unlocking
User pushes door handle sw. •
•
ECU sends LF-challenge via exterior antenna.
•
FOB sends RF-response to the ECU.
•
Door unlocking status is engaged.
•
Doors are opened.
LF
Figure 2
RF
FOB
Page 4
2.2.Engine Start
User operates the engine start knob. •
•
ECU sends LF-challenge via interior antenna.
•
FOB sends RF-response to the ECU.
•
Immobilizer ECU receives and authorize the response.
•
Engine controller ECU receives the authorization for engine strat.
•
Start the engine.
RF
LF
FOB
Figure 3
2.3.Engine Stop
User operates the engine stop knob. •
•
ECU communicates with the other ECU for engine start request.
•
Engine controller ECU receives the request.
•
Stop the engine
Figure 4
Page 5
2.4.Door Locking (Push switch)
User closes the door and pushes the switch (sensing of door locking switch). •
•
ECU sends LF-challenge via exterior antenna.
•
FOB sends RF-response to the ECU.
•
Door locking status is engaged.
•
Doors are locked.
•
(Indicates the door locking status by means of Flasher / Buzzer or stuff)
Figure 5
Page 6
3.Active Access Entry Functionality
3.1.Door Unlocking
Same functionality as the current one.
3.2.Engine Start
This function does not effect on the active entry system.
3.3.Engine Stop
This function does not have influence on the active entry system.
3.4.Door Locking
Same functionality as the current one.
Page 7
A
r
r
r
r
A
r
r
r
A
4.Entry System Options
4.1.System Schematic
4.2.Modules
4.2.1.FOB ECU
OTHER ECUS
Body Bus
ECUECUECU
315MHz
125kHz
Y
Local Bus
RF
Amp
X
LF
Amp
ENTRY SYSTEM ECU
Tuner signal
FOB
ASIC
Lock
Unlock
Panic
Emergency key (Transponder)
FOB
125kHz
LF (>2Kbps)
RF Tuner
315MHz
RF (>4Kbps)
4.2.2.Entry System ECU
Dr Door handle
s Door handle
Back Door handle
Push knob
(Engine start knob)
Body Bus
Local Bus
MCU
ENTRY SYSTEM ECU
Tuner signal
Room1
Excite
Room2 Room3
LF
Excite
Dr
LF
Excite
LF
LF
Excite
LF
Excite
s
LF
Excite
Room4
Excite
PBD
LF
Interior Antenna
Room1: Cockpit
Room2: 2nd Row
Room3: Console
Room4: 3rd Row
125kHz
Exterior Antenna
Dr : Driver Door Antenna
s : Assist Door Antenna
Back Door : Bumper Antenna
Page 8
5.System Characteristics
5.1.Antenna Areas
Exterior operating range: 0.8m to 1.5m
Interior operating range: Only inside the car
Number of the exterior exciters : typ.3, however, it is depending on the type of the vehicle.
Number of the interior exciters: max.4 (min.2)