J1939#
J1939 is an extension of the canbus protocol with well defined ID codes and offset values. J1939 is typically used in heavy trucking.
mod |
Field |
Operators |
Example |
|---|---|---|---|
j1939 |
Priority |
== != < > <= >= |
j1939 Priority==1 |
j1939 |
DP |
== != < > <= >= |
j1939 DP != 1 |
j1939 |
EDP |
== != < > <= >= |
j1939 EDP == 0 |
j1939 |
PDU |
== != < > <= >= |
j1939 PDU != 0x234 |
j1939 |
PF |
== != < > <= >= |
j1939 PF != 220 |
j1939 |
PS |
== != |
j1939 PS == true |
j1939 |
SRC |
== != < > <= >= |
j1939 SRC != 0x123 |
j1939 |
Data |
~ !~ |
j1939 Data ~ TEST |
Example Search#
The following search will extract the engine temperature from J1939 bus traffic and display the slope of the curve in a chart over time. This query would be extremely useful in fleet management in identifying trucks that heat up more quickly than others, potentially indicating a maintenance problem.
tag=trucks j1939 EDP==0 PF==254 Data | slice uint16be(Data[2:3]) as engine_oil_temp | variance engine_oil_temp by SRC over 30s | chart variance by SRC