TELTONIKA FMB641 Computer Network Protocol Instructions
- June 21, 2024
- teltonika
Table of Contents
TELTONIKA FMB641 Computer Network Protocol
Specifications
- Model: FMB641
- Interface: Controller Area Network (CAN) Supported Vehicle Brands: Mercedes Benz, Volvo, MAN, DAF, Iveco, Scania, Renault
- Available Parameters: Total Fuel, Total Distance, Status of brake pedal, Engine Torque, Actual fuel, Accelerator pedal position, Status engine brake, Speed, RPM, Engine hours, Vehicle Weight, Fuel level, Tachograph data
- CAN Message ID Type : Standard ID (0 to 0x7FFh) and Extended ID (0 to 0x1FFFFFFFh)
Introduction
Controller Area Network (CAN or CAN-bus) is a computer network protocol and bus standard designed to allow microcontrollers and devices to communicate with each other without a host computer. It was designed specifically for automotive applications but is now also used in other areas.
SAE J1939 and J1708* is the vehicle bus standard used for communication and diagnostics among vehicle components. Based on the same architecture FMS protocol dedicated to telematics systems is available. It has certain standardized parameters available, such as fuel consumption, engine work hours, etc. Please visit http://www.fms-standard.com/ for more information and message structure.
The FMS interface is an optional interface for different truck manufacturers. Supporting information is dependent upon vehicle equipment. For the full information set, additional Electronic Control Units (ECU) may be required. Please contact the manufacturer or your dealer for more details.
Vehicle brands supported:
- Mercedes Benz Volvo
- MAN
- DAF
- Iveco
- Scania Renault
Available parameters:
- Total Fuel
- Total Distance
- Status of brake pedal
- Engine Torque
- Actual fuel
- Accelerator pedal position
- Status engine brake
- Speed
- RPM
- Engine hours Vehicle Weight
- Fuel level Tachograph data
The availability of parameters depends on the vehicle’s model and
configuration of the FMS interface of the truck.
J1708 is an additional FMS protocol used by some vehicle manufacturers. If
your vehicle supports J1939 and J1708 both protocols then you must disable
J1708 in configuration to receive fuel data.
General description
- CAN works if no USB cable is inserted and isn’t in deep sleep mode;
- Uses six different speeds: 50 kbps, 100 kbps, 125 kbps, 250 kbps, 500 kbps, 1000kbps; Auto Baud rate detection;
- Filtering messages (StId, ExtId) according to configuration;
- Using a mask, filters required bytes;
- Different CAN configurations.
Configuration
FMB641 has 70 configurable Manual CAN elements.
CAN message ID type: Message ID type two types according to SAEJ1939
standard: Standard ID (value: M to Mx7FFh) and Extended ID (value: 0 to
0x1FFFFFFFh).
Message ID value is entered in HEX format. This parameter is used to configure
the hardware message filter. All messages contain 8 bytes of data, to select
particular data/bytes “Output Data Mask” is used, it’s done by ticking the
required bytes, and only selected bytes are sent to the server.
Example: A sample CAN message has the following structure:
X18FEE9018FFFFFFFF23840300, where essential parts are FEE9 – identifier and
FFFFFFFF23840300 – data bytes.
CAN messages are configured like any other I/O parameters. They consist of 4
identifier bytes and 8 data bytes. Below you will find a sample configuration
for the fuel consumption parameter:
- ID type – is always 29 bits.
- Output data mask – defines which data bytes are sent to the server (sometimes not all data bytes are necessary).
- CAN ID – this is a 4-byte identifier. Messages use 4 bytes, but the first and last bytes may differ in different vehicle models while the middle four bytes are the same for all vehicles. The first and last bytes may have any value. Because of this reason, it is recommended to write FF in the first byte and the same in the last byte.
Example
All Mercedes Benz Actros 2 models with Vehicle Identification Number (VIN)
starting with WDB93 can connect the FMB641 module to the CAN bus. This can be
done by connecting to a special PSM module (which may or may not be included
in the truck) or ground module of the vehicle. For the CAN signal to be
available, parameter 520 must be enabled in
“kommunikationsschnittstelle” in the vehicle with Mercedes Star diagnosis.
CAN wires can be found on the X5 connector located in the fuse box:
- PIN 5: CAN Low signal (yellow wire)
- PIN 2 : CAN High signal (blue wire)
In the example, FMB641 will filter all CAN messages with the identifier FFFEE9FF (fuel consumption).
Note: Averaging constant cannot be used with CAN data because this
information comes in digital format. So to prevent data loss, set the
Averaging constant parameter to 1.
Most parameters have a certain resolution. The FEE9 parameter has 0.5L/bit
gain, so the value that is sent to the server has to be multiplied by 0.5.
Data parsing is preceded by selecting the correct message from all available on the CAN bus. FMS standard interface description indicates that fuel consumption is a parameter with ID FEE9:
Note: This information is provided only as an example and Teltonika takes
no responsibility for information accuracy or damage that may be done to the
vehicle or FMB641 module while integrating it.
https://wiki.teltonika-gps.com/view/FMB641_Manual_CAN_IO
FAQ
- Q: How do I know if my vehicle supports J1939 and J1708 protocols?
- A: If your vehicle supports both protocols, you must disable J1708 in the configuration settings to receive fuel data.
- Q: What should I do if I encounter issues with CAN message configurations?
- A: If you face difficulties with CAN message configurations, refer to the FMB641 user manual for detailed instructions or contact the manufacturer for assistance.