Does the absence of a terminating resistor on the CAN bus of the BMS control board affect its anti-interference capability?

The absence of terminating resistors or mismatched terminating resistors on the CAN bus significantly reduces its interference immunity. The primary function of terminating resistors is impedance matching, eliminating signal reflections, and preventing waveform distortion and ringing. Ringing generates high-frequency noise and degrades signal quality, making the bus more susceptible to interference. Furthermore, mismatch leads to bus imbalance, reducing the common-mode rejection ratio of differential receivers and making them more sensitive to common-mode interference. Therefore, a 120Ω terminating resistor must be installed at each end of the bus. This is fundamental for ensuring CAN bus signal quality, reliable communication, and good EMC performance, and is especially important in harsh electromagnetic environments such as automotive networks.