The TCAN1043xx-Q1 devices are able to detect the following six faults that can occur on the CANH and CANL bus terminals. These faults are only detected in Normal mode, and are only indicated via the nFAULT terminal while in Normal mode.

1. CANH bus pin shorted V_SUP
2. CANH bus pin shorted V_CC
3. CANH bus pin shorted GND
4. CANL bus pin shorted V_SUP
5. CANL bus pin shorted V_CC
6. CANL bus pin shorted GND

These failures are detected while transmitting a dominant signal on the CAN bus. If one of these fault conditions persists for four consecutive dominant bit transmissions, the nFAULT indicates a CAN bus failure flag in Normal mode by driving the nFAULT pin low. The CAN bus driver remains active.

The bus fault failure circuitry is able to detect bus faults for a range of differential resistance loads (R_CBF), for data rates from 250kbps to 1Mbps, and within nominal temperature conditions (25°C to 60°C). Outside of these ranges, the CAN bus fault detection circuitry becomes less reliable, potentially reporting CAN bus faults when there are none present.