Position Determination Of Transmitter Key, Basic Function - GF80.20-P-1009A
Model All (4xWD, CAR)
Overview
This document contains information on:
- General
- Function
- Vehicles with KEYLESS-GO
- Vehicles with KEYLESS-GO in smartphone
Sample illustration of key detection areas
| Zone | KEYLESS-GO | KEYLESS-GO on smartphone |
|---|---|---|
| Zone 1 | Distance > 6 m - No SmartKey Recognition. | Distance > 10 m - Connection with authorized device. |
| Zone 2 | Distance 3...6 m - Proximity detection active. | Distance < 4 m - Position finding of authorized device. |
| Zone 3 | Distance < 3 m - SmartKey Recognition active, vehicle opens. | Distance of 3...4 m - Vehicle opens. |
General
Vehicles with KEYLESS-GO:
The position of the transmitter key is also precisely determined when outside the vehicle.
Vehicles with vehicle access and drive authorization via mobile phone:
If the Digital Vehicle Key (mobile phone or Digital Vehicle Key Sticker) is used, start enable is only granted if the authorized device is located in the vehicle.
Function
Vehicles with KEYLESS-GO
The position search for the transmitter key is activated when the driver requests start enable.
An antenna in the vehicle interior transmits radio signals. They are received by the transmitter key. The antenna and the transmitter key then exchange encrypted data.
If the transmitter key is not located in the vehicle interior, the start enable is not issued.
The position search for the transmitter key is also activated when the following actions are performed:
- Open door.
- Open trunk lid or tailgate.
- Unlock or lock vehicle via the central locking system.
The transmitter key receives signals from the vehicle from a distance of six meters.
The vehicle remains locked while the transmitter key is between three and six meters from the vehicle. However, personalized settings are already being transmitted and, depending on the equipment installed, the retractable door handles extend outward.
If the distance to the key reduces further and this is located for longer than two seconds in zone 3, the vehicle is unlocked. Multiple antennae located at the side, front, and back of the vehicle transmit radio signals.
The transmitter key receives the signals from the antenna located near it. This antenna and the transmitter key then exchange encrypted data.
The position of the transmitter key is verified by evaluating the signal levels of the radio signals and can thus be determined accurately.
The wireless connection between the key and vehicle is interrupted if the key takes longer than 2 minutes to change from zone 2 to zone 3. After 1 to 2 minutes in zone 3, "Smart Unlock" is no longer available.
If the key leaves the 6 meter detection range within 5 minutes of the end of a journey, the wireless connection is directly ended.
However, if the key remains within the detection range for 72 hours, the transmission power of the vehicle is halved and the total detection distance is reduced from 6 meters to 4.20 meters.
The wireless connection is stopped after 408 hours inside the detection range. The vehicle must then be actively unlocked to restart the wireless connection.
Vehicles with KEYLESS-GO in smartphone
The Bluetooth® antennas installed in the vehicle are used to continuously search for an authorized smartphone. If an authorized smartphone is detected within the range of Zone 1, a connection is established.
In Zone 2, localization is performed at a distance of approx. 4 m to the vehicle over corresponding UWB antennas. The direction from which the smartphone approaches the vehicle is also taken into account.
Within Zone 3, as of a range of 3...4 m, the following functions are triggered by the vehicle, depending on the equipment involved:
- Actuation of light
- Extending of door handles
- Unlocking of vehicle
Further antennas in the vehicle interior verify the location of the authorized smartphone before enabling drive authorization. All permissions required for drive authorization are stored in the KEYLESS-GO mobile device connection control unit. Communication for enabling the drivetrain takes place between the electronic ignition lock and the KEYLESS-GO mobile device connection control unit.
If the vehicle is loaded with a large percent by volume of metal, the radio signals emitted by the antennae may be strongly reflected or absorbed. This can cause incorrect detections.
In vehicles with KEYLESS-GO, the maximum overlap between the inside and outside areas (measured at the side window) is approx. 10 cm depending on the vehicle contour. This means that the transmitter key is definitively either within or outside the vehicle above 10 cm. At less than 10 cm (gray zone), the transmitter key position determination may be faulty.
| Function schematics | |||
| Function schematic for detection of transmitter key position | Model 118, 167, 177, 243, 247 | PE80.20-P-2503-97A | |
| Model 293 | PE80.20-P-2503-97B | ||
| Model 206, 214, 223, 236, 254, 294, 295, 296, 297 | PE80.20-P-2503-97C | ||
| Model 213, 238, 257, 290 as of model year 2021 | PE80.20-P-2503-97E | ||
| Model 464 | PE80.20-P-2503-97F | ||
| Model 192, 232 | PE80.20-P-2503-97G | ||
| Further basic functions | |||
| Electronic ignition lock control unit, basic function | GF80.57-P-9890A | ||
| KEYLESS-GO control unit, basic function | Model 293 | GF80.61-P-9891A | |
| Transmitter key, basic function | GF80.35-P-2001A | ||
| KEYLESS-GO antenna, basic function | Model all (4xWD) Model all (CAR) with code 889 (KEYLESS-GO) Model all (CAR) with code 893 (KEYLESS-Start) Model all (CAR) with code P17 (KEYLESS-GO package) |
GF80.61-P-2001A | |
| Transceiver basic function | Model all (4xWD) Model all (CAR) with code 889 (KEYLESS-GO) Model all (CAR) with code 893 (KEYLESS-Start) Model all (CAR) with code P17 (KEYLESS-GO package) |
GF80.61-P-2021A | |
| Rear switch module, basic function | Model all (CAR) with code 871 (Sensor system for trunk lid opening/closing) |
GF80.61-P-9890A |