What causes the entire CAN bus to fail?

Usually a shorted wire or a failed module that pulls the entire bus voltage to ground. Water damage is another common cause.

How do I diagnose a CAN bus issue?

Measure CAN H and CAN L voltages with a multimeter. They should be ~2.5V and ~2.5V (inverted). If both are at 0V or 5V, there is a short.

Critical

Network/Communication System

The entire CAN bus network has stopped communicating. Major system failure.

Common Fix

Repair CAN bus wiring

Estimated Cost (DIY)

$50 - $500

CAN bus wiring short or openlikely

Failed module pulling bus downpossible

Water damage to wiringpossible

Need to read or clear this code?

What causes the entire CAN bus to fail?: Usually a shorted wire or a failed module that pulls the entire bus voltage to ground. Water damage is another common cause.
How do I diagnose a CAN bus issue?: Measure CAN H and CAN L voltages with a multimeter. They should be ~2.5V and ~2.5V (inverted). If both are at 0V or 5V, there is a short.

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