Damaged or chafed wiring harness on Bus E, often from rubbing against metal components or improper routing; Corroded or loose connector pins at a module or inline connector on Bus E; Internal short inside a module connected to Bus E, such as the infotainment or body control module; Water intrusion into a connector or module causing a short to power or ground; Aftermarket accessories improperly tapped into the Bus E wiring; Failed termination resistor or shorted CAN transceiver within a module

DTC codes / U00xx · Network wiring and bus faults / U0072

U0072Vehicle Communication Bus E (shorted to Bus E)

Q: What does code U0072 mean?

Vehicle Communication Bus E (shorted to Bus E). U0072 is a generic network communication code indicating that the vehicle's control modules have detected a short circuit on Communication Bus E, one of the CAN (Controller Area Network) data buses used for module-to-module messaging. The computer sets this code when the Bus E wiring is shorted to another bus, power, or ground, disrupting normal communication.

U0072 is a generic network communication code indicating that the vehicle's control modules have detected a short circuit on Communication Bus E, one of the CAN (Controller Area Network) data buses used for module-to-module messaging. The computer sets this code when the Bus E wiring is shorted to another bus, power, or ground, disrupting normal communication.

SystemNetwork

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

AreaNetwork wiring and bus faults

Symptoms you may notice

Multiple warning lights illuminated on the dashboard, often including the check engine light, ABS, and traction control
Intermittent or complete failure of systems that rely on Bus E, such as infotainment, climate control, or driver-assist features
The engine may start and run, but some accessories or modules may not respond
A no-start condition if the shorted bus prevents critical modules from communicating
Often no symptoms besides the warning light if the short is intermittent or affects a non-essential module
Erratic behavior of electronic features like radio, windows, or instrument cluster

Common causes, most likely first

Damaged or chafed wiring harness on Bus E, often from rubbing against metal components or improper routing
Corroded or loose connector pins at a module or inline connector on Bus E
Internal short inside a module connected to Bus E, such as the infotainment or body control module
Water intrusion into a connector or module causing a short to power or ground
Aftermarket accessories improperly tapped into the Bus E wiring
Failed termination resistor or shorted CAN transceiver within a module

How to diagnose and fix it

Use an OBD-II scan tool to read all codes and identify which modules are offline or reporting communication faults
Obtain the factory wiring diagram for Bus E and locate all connectors and modules on that bus
Visually inspect the Bus E wiring harness for damage, chafing, or corrosion, especially near moving parts and connectors
Disconnect modules one at a time to see if the short disappears, isolating the faulty component
Measure resistance and voltage on the Bus E CAN lines to check for shorts to power, ground, or between buses
Repair or replace damaged wiring, connectors, or the shorted module as needed
Clear codes and perform a road test to verify communication is restored and the code does not return

What most technicians overlook with U0072

A shorted Bus E often causes other modules to set communication codes, so always diagnose the root cause rather than replacing modules that are merely victims of the short.
The short may be intermittent and only appear when the vehicle is driven over bumps or in wet conditions, so wiggle-testing the harness while monitoring live data is crucial.
Aftermarket alarms, remote starters, or audio equipment are common culprits because they are often spliced into bus wiring without proper isolation.
Bus E is sometimes used for specific functions like entertainment or driver assistance, so a failure may not disable the engine but can affect safety systems.
A faulty module can short the bus internally even when powered off, so disconnecting modules is a reliable isolation method.

Can I keep driving with U0072?

If the vehicle runs and drives normally, you can drive it to a repair shop, but avoid using affected electronic features and be prepared for possible intermittent failures. If multiple systems are disabled or the engine stalls, stop driving and have the vehicle towed to prevent unsafe operation.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.