We have developed a unique Bluetooth module that can be used to make the audio equipment of Saabs smart. The device is connected to the cables of the factory head unit and uses a CAN-BUS connection to establish a wireless audio connection with the hi-fi equipment that originally did not have such a function. With its help, you can listen to music and online radio from mobile devices in such a way that the original comfort functions of the vehicle are preserved (for example, you can scroll through the tracks from the steering wheel), and even functions that did not exist until now appear. During use, the information display (SID) can display the metadata of the music tracks, such as the name of the artist, album, track title. The displayed information can be configured individually and even a custom caption can be written.
How does it work?
Depending on the type of Saab the BT Changer works in two ways:
- In the case of OG 9-3/9-5 types, it is connected to the CD changer (CD storage) line of the factory head unit and pretends to be a CD storage by communicating with the system via CAN. This makes many CD Changer functions available and even some new functions may appear via the I-BUS system. Of course, the factory CD Changer function is unfortunately lost along with this, but it can also be installed on the model that did not originally have a CD storage.
- For post-2006 NG 9-3 and OG 9-5 models, the BT Changer unit connects to the satellite radio line and communicates with the system via CAN, pretending to be XM radio. New functions may also appear via I-BUS system. If there was an XM radio in the car, it unfortunately has to be disconnected, the two do not work together.
Does it work as a hands-free device?
BT Changer is currently just an audio receiver. For example, when playing music from the phone, the music fades out during an incoming call, and then picks up again at the end of the call. So it cannot be used as a hands-free device at the moment. But the hardware is also suitable for a two-way connection, so it can even work as a hands-free speaker in Bluetooth mode. In this case, it will be necessary to install an additional microphone. This feature is currently not active. but the included cable harness is prepared for this. This will be available in the future and can be activated with a software update.
Is it upgradeable?
The module can be updated or adapted via a WI-FI connection. For example, the type of the head unit and the SID must be set this way.
The BT Changer can communicate on three lines:
- CAN-BUS connection with the vehicle
- Transmits between the factory head unit and the mobile device via a Bluetooth connection
- On a WI-FI connection with the mobile device.
How to connect it?
There is no need to cut the wire for connection, it is only necessary to connect it to the cable harness behind the head unit by soldering or with the optional connectors (only available for some models). After installing the BT Changer, the CD Changer must be unplugged (if there is no such unit, there is nothing to do). In the connection descriptions corresponding to the types, the colors of the cables to be connected are marked exactly, so the installation can be done at home with a little dexterity. After connection, the device is ready for use.
Which car types can it be used for?
BT Changer is currently only available for certain Saab models.
Why is this better than a head unit replacement?
Experience shows that premium category vehicles – such as Saabs – are factory-fitted with high-quality hi-fi equipment (e.g. Harman Kardon, Bose, etc.). However, modern audio equipment at the time lacked the now indispensable Bluetooth connection. It is unnecessary to change the head unit just for this function, which also has several disadvantages. The fitting is difficult, control from the steering wheel can only be solved with difficulty or not at all. In addition, some models receive the date corresponding to the service intervals from the factory head unit, so if it is replaced, this function is lost.
These problems do not occur with the BT Changer module. Installation is simple and much cheaper than replacing and fitting a new head unit.
BT Changer is a Hungarian startup. We welcome any feedback regarding its operation. Our goal is to tailor the device’s functions even more to the users’ needs. In the future, we plan to adapt it to the pre-2006 Saab 9-3 head unit, as well as to other brands.