CANxx Commands
Command family for reading CAN parameters from the vehicle’s ECU.
What is it for?
| Use case | Description |
|---|---|
| 🚛 Heavy vehicles | CAN00/CAN03 for trucks and buses with J1939 protocol |
| 🚗 Light vehicles | CAN01 for cars with OBD-II/J1850 protocol |
| 🚚 Trailers and semi-trailers | CAN02 for ABS/EBS systems in semi-trailers |
| ⛽ Fuel consumption | CAN05 for FuelRate and MAF sensor reading |
| 📋 Report integration | CAN03 in fixed-width format for Ux reports |
General Description
The CANxx commands allow obtaining vehicle information through the CAN bus. Each variant is optimized for different protocols and data formats:
| Command | Protocol | Main Use |
|---|---|---|
| CAN00 | J1939 | Commercial/heavy vehicles |
| CAN01 | J1850/OBD-II | Light vehicles |
| CAN02 | EBS/ABS | Trailers and semi-trailers |
| CAN03 | J1939 (fixed width) | Ux report integration |
| CAN05 | Generic | FuelRate and consumption |
Before using these commands, configure the CAN bus through CXCAN.
CAN00 - J1939 Parameters
Reading of standard parameters using J1939 protocol for commercial and heavy vehicles.
Query
QCAN00Response
RCAN00 2010=value,5000=value,1030=value,4201=value,1020=value,1010=value,2012=value,2013=value,2020=value,3010=valueParameters
| ID | Parameter | Format |
|---|---|---|
2010 | RPM | 4-digit integer |
5000 | Accelerator position (%) | 2-digit integer |
1030 | Odoliter (L) | 8 digits + 2 decimals |
4201 | Fuel level (%) | 2-digit integer |
1020 | Odometer (Km) | 6 digits + 2 decimals |
1010 | Wheel speed (Km/h) | 3 digits max |
2012 | Coolant temp (ºC) | 2-digit integer |
2013 | Oil pressure (kPa) | 3-digit integer |
2020 | Engine ON time (s) | 6 digits max |
3010 | Trip fuel (L) | 8 digits + 2 decimals |
Example
>RCAN00 2010=1000,5000=00,1030=10000.00,4201=50,1020=20000.00,1010=60,2012=15,2013=100,2020=13,3010=0.13<CAN01 - OBD-II Parameters
Reading using J1850/OBD-II protocol for light vehicles.
Query
QCAN01Response
RCAN01 1=value,2=value,3=value,B=value,14=value,15=value,2A=value,2C=valueParameters
| ID | Parameter | Format |
|---|---|---|
1 | VIN | 16-digit ASCII |
2 | RPM | 4-digit integer |
3 | Wheel speed (Km/h) | 3 digits max |
B | Odometer (Km) | 6 digits + 2 decimals |
14 | Odoliter (L) | 8 digits + 2 decimals |
15 | Fuel level (%) | 2-digit integer |
2A | Coolant temp (ºC) | 2-digit integer |
2C | Oil pressure (kPa) | 3-digit integer |
Example
>RCAN01 1=2SA23000L2,2=1000,3=60,B=20000.00,14=100000.00,15=50,2A=15,2C=100<CAN02 - Trailer Parameters
Specific reading for trailers and ABS/EBS brake systems.
Query
QCAN02Response
RCAN02 red=value,amber=value,axle_load=value,whell_speed=v1|v2|v3|v4,vehicle_speed=value,dtc_0=value,dtc_1=valueParameters
| Field | Parameter | Description |
|---|---|---|
red | Red Warning Lamp | Red warning lamp |
amber | Amber Warning Lamp | Amber warning lamp |
axle_load | Axle Load | Load per axle |
whell_speed | Wheel Speed | Speed of 4 wheels (separated by |) |
vehicle_speed | Vehicle Speed | Vehicle speed |
dtc_0 | DTC 0 | Diagnostic trouble code 0 |
dtc_1 | DTC 1 | Diagnostic trouble code 1 |
Example
>RCAN02 red=0,amber=1,axle_load=5000,whell_speed=60|60|59|61,vehicle_speed=60,dtc_0=0,dtc_1=0<CAN03 - Fixed-Width Format
Reading in fixed-width format, ideal for integration with Ux user reports.
Query
QCAN03Response
RCAN03 aaaabbbcccddddddddeeefffggghhhhhhhiiiiiiiijjjjjjjjkkParameters
| Field | Length | Parameter | Format | Unit |
|---|---|---|---|---|
aaaa | 4 | Engine Speed | Decimal | RPM |
bbb | 3 | Accel PCT | Decimal | % |
ccc | 3 | Fuel PCT | Decimal | % |
dddddddd | 8 | Odometer Total | Hex | meters |
eee | 3 | Speed | Decimal | Km/h |
fff | 3 | Engine Temp | Decimal | °C |
ggg | 3 | Oil Press | Decimal | kPa |
hhhhhhh | 7 | Time Engine On | Hex | seconds |
iiiiiiii | 8 | Fuel Trip | Hex | liters |
jjjjjjjj | 8 | Odoliter Total | Hex | liters |
kk | 2 | Age | Hex | seconds |
Hexadecimal fields must be converted to decimal. For example, if dddddddd = 0001E240, the odometer is 123456 meters.
Example
>RCAN03 15000350501234567806008510000012302345678001234560A<CAN05 - FuelRate
Reading of fuel consumption rate (FuelRate).
Query
QCAN05Response
RCAN05 FR_HW=value,FR_SW=value,MAF=valueParameters
| Field | Parameter | Description | Unit |
|---|---|---|---|
FR_HW | FuelRate Hardware | Direct sensor reading | L/h |
FR_SW | FuelRate Software | MAF-based calculation | L/h |
MAF | Mass Air Flow | Air flow sensor | g/s |
Example
>RCAN05 FR_HW!3,FR_SW=89.60,MAF=300.00;ID=869084063093789;*5A<The FR_SW is calculated from the MAF sensor when the direct hardware value is not available.
Error Codes
Common to all CANxx commands:
| Code | Description |
|---|---|
=value | Valid value |
=NaN | Parameter not read (CAN01) |
!1 | Process error |
!2 | Unknown parameter |
!3 | No information available |
Code !3 generally indicates that the vehicle doesn’t support the parameter or there’s a physical connection problem with the CAN bus.
Compatibility
See Also
- CXCAN Command - CAN bus configuration
- ECU Command - Flexible CAN variable reading
- CXECU Command - ECU configuration
- Ux Command - Custom user reports