J1939 Cable Impedance: Why 120Ω Is Non-Negotiable in CAN Bus Design
A 40-meter off-highway vehicle backbone is plagued by intermittent CAN errors. ECUs drop off the network randomly under high load, bringing operations to a halt. The design team verifies the network: the 120Ω terminators at both ends are precision metal-film components, verified flawlessly with a multimeter. The logic seems unassailable: 120Ω resistors mean a 120Ω … Read more