ESD protection circuit, fault detection, voltage divider network, mobile devices

The Maxim Integrated family of CAN transceivers incorporate a fault detection feature where it monitors the CANH and CANL line for faults like overcurrent, overvoltage, and transmission failure. When a fault is detected, the FAULT pin goes high, which triggers an external interrupt with the local CAN controller, and the driver and receiver lines are placed in recessive mode. 

https://www.futureelectronics.com/npi/max3301x