Improper use of J1939 cable may cause communication failures

Improper use of J1939 cable may cause communication failures

J1939 cable, as a dedicated communication cable based on CAN bus protocol, is widely used in electronic control systems of heavy vehicles, engineering machinery, and industrial equipment. If used improperly, it may cause communication failures:

Signal transmission interruption

If the shielding layer of J1939 cable is damaged or poorly grounded, it can cause electromagnetic interference (EMI) to invade, leading to signal attenuation or noise interference. For example, in the hydraulic control system of construction machinery, if the cable shielding layer is damaged, it may cause a sharp increase in the error rate of CAN bus messages, leading to the failure of engine speed control or abnormal action of hydraulic valves.

Network topology disorder

The J1939 protocol requires bus terminal resistance matching. If the cable length does not meet the standard or the terminal resistance is missing, it may cause signal reflection, resulting in communication nodes misjudging messages. For example, in a commercial fleet, if the CAN bus of some vehicles is not terminated due to long cables, it may cause communication interruption among the entire fleet's ECU.