Data Bus

The shared wiring the vehicle's computers talk over — most commonly a twisted pair carrying CAN, plus slower single-wire links for less urgent traffic. Rather than run a wire per value, each module broadcasts what it knows on a schedule and the others listen for what they need, so engine speed, road speed, throttle position and torque all travel as messages rather than as voltages. Two consequences follow. A fault in the bus itself affects every module hanging off it at once, which is why a page of unrelated codes is usually one fault. And a module that has lost its power or its earth reports identically to one that has failed, because silence is silence — which is why lost communication codes are so often a supply problem rather than a module.

Also known as: can bus, canbus, controller area network, network, data link, lin bus, bus wiring, comms

Referenced by 563 codes

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Codes involving this component (563)

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CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.

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