The SAE J1939 DBC file contains conversion rules for scaling raw J1939 data to human-readable form (km/h, %, degC, ...).
DBC is the standard CAN database file format used in most CAN tools - incl. our CAN logger software/APIs.
This download includes a legal J1939 DBC file & license, based on the J1939 Digital Annex (priced at 250$). We offer the J1939 DBC as part of a re-sale partnership with SAE.
Quickly convert J1939 data with broad DBC software support
The extensive DBC contains 1,000+ PGNs and 6,400+ SPNs
Use the Google Sheet to check if your PGNs are covered
Benefit from free corrections based on large user base
Avoid manually constructing a J1939 DBC from scratch
Includes legal license similar to the J1939 Digital Annex (price: 250$)
A *.DBC file is a standardized method for storing the “rules” on how to interpret raw CAN bus data. In particular, it contains details on what ‘signals’ (e.g. RPM, Vehicle Speed, …) are contained within which ‘messages’ (i.e. CAN IDs).
In the J1939 standard, messages are referred to as Parameter Group Numbers (PGNs) and signals as Suspect Parameter Numbers (SPNs).
Further, a DBC file includes names, descriptions, positions and lengths of the signals - as well as how to offset & scale them. In short, the J1939 DBC file is key to decoding your data.
This J1939 DBC file bundle includes:
If you have a list of CAN IDs from a J1939-based vehicle, you can paste them in our 'CAN ID to J1939 PGN converter':
See also our FAQ for details on PGN vs. SPN coverage.
Below you’ll find a J1939 data log from a truck recorded with the CANedge2. The sample also contains a demo J1939 DBC with EngineSpeed + WheelBasedVehicleSpeed.
You can load the raw data & DBC in the free asammdf GUI, decode it to human-readable form and plot it.
|Standard(s)||J1939 Digital Annex (2020-03) - corresponds mainly to J1939-71|
|Multipacket||Multipacket syntax is used for the multipacket PGNs included in the DBC|
|Multiplex||Some multiplexed messages are included, but with "regular" syntax (not multiplex)|
|Descriptions||Partial SPN descriptions included in DBC (full included in Digital Annex)|
|Attributes||SPN ID, VFrameFormat|
|Value tables||Only partially included|