A short to ground on the D (+) data wire, often caused by chafed insulation rubbing against a metal bracket or body panel; A failed control module that is internally shorting the D (+) line to ground, pulling the entire bus down; Corroded, loose, or damaged connector pins at any module or inline harness connector on the bus; Water intrusion into a connector or module housing, leading to corrosion and a low-resistance path to ground; Aftermarket accessories improperly tapped into the data bus wiring, creating an unintended ground connection; A faulty terminating resistor inside a module that alters bus voltage levels and mimics a short; Broken or crushed wiring harness from a prior repair or collision damage

DTC codes / U00xx · Network wiring and bus faults / U0058

U0058Vehicle Communication Bus D (+) Low

Q: What does code U0058 mean?

Vehicle Communication Bus D (+) Low. U0058 is a generic network communication code indicating that the vehicle's primary communication bus, often called the CAN (Controller Area Network) bus, has a low voltage condition on its D (+) data line. The computer that set this code detected that the positive data wire was persistently at or near ground potential instead of toggling between the normal high and low voltage states, which prevents modules from exchanging messages reliably.

U0058 is a generic network communication code indicating that the vehicle's primary communication bus, often called the CAN (Controller Area Network) bus, has a low voltage condition on its D (+) data line. The computer that set this code detected that the positive data wire was persistently at or near ground potential instead of toggling between the normal high and low voltage states, which prevents modules from exchanging messages reliably.

SystemNetwork

Code typeGeneric (all makes)

SeverityHigh

Fix difficultyProfessional

AreaNetwork wiring and bus faults

Symptoms you may notice

Multiple warning lights illuminated simultaneously, including the check engine light, ABS, airbag, and traction control lamps
The engine may start and run, but various electrical accessories such as the radio, windows, or climate control may behave erratically or not work at all
Intermittent or complete failure of dashboard gauges and instrument cluster displays
The transmission may default to a limp mode or fail to shift properly due to lost communication with the powertrain control module
Often no symptoms besides the warning light if the fault is intermittent or affects only a non-critical module
The scan tool may be unable to communicate with some or all control modules on the bus

Common causes, most likely first

A short to ground on the D (+) data wire, often caused by chafed insulation rubbing against a metal bracket or body panel
A failed control module that is internally shorting the D (+) line to ground, pulling the entire bus down
Corroded, loose, or damaged connector pins at any module or inline harness connector on the bus
Water intrusion into a connector or module housing, leading to corrosion and a low-resistance path to ground
Aftermarket accessories improperly tapped into the data bus wiring, creating an unintended ground connection
A faulty terminating resistor inside a module that alters bus voltage levels and mimics a short
Broken or crushed wiring harness from a prior repair or collision damage

How to diagnose and fix it

Connect a scan tool and record all stored codes and freeze-frame data from every module that responds, noting which modules are offline
Visually inspect the D (+) data wire and all related connectors for chafing, corrosion, water intrusion, or loose pins, starting at the modules that are not communicating
Disconnect the battery and measure resistance from the D (+) wire to chassis ground at the diagnostic link connector (DLC) to check for a direct short
Isolate sections of the bus by disconnecting modules one at a time and rechecking the D (+) voltage or resistance to identify a module that is pulling the line low
Repair any damaged wiring, replace corroded terminals, and reseal connectors to prevent future water intrusion
If a module is found to be internally shorted, replace or reprogram that module according to the manufacturer's procedures
Clear all codes and perform a road test to verify that communication is restored and no codes return

What a low D (+) line really tells you

A low D (+) line does not always mean the wire itself is shorted; a single failed module can hold the entire bus low, so disconnecting modules one by one is often the fastest way to find the culprit.
Many technicians replace the PCM or BCM first when communication codes appear, but the fault is more often in a connector or a non-critical module such as a door control module or seat memory module.
The D (+) and D (-) wires are a twisted pair, and a short between them or a swapped connection during a previous repair can set this code even though the wiring looks intact.
Aftermarket alarms, remote starters, or fleet tracking devices tapped into the CAN bus are a common hidden cause, especially if the code appeared shortly after installation.
A weak or failing battery or poor ground connection can cause bus voltage to sag low enough to set U0058 without any actual wiring fault, so always verify battery and ground integrity first.

Can I keep driving with U0058?

Do not drive the vehicle if multiple warning lights are on or if the engine runs poorly, because lost communication can disable safety systems and cause unpredictable behavior. If the vehicle drives normally and only the warning light is on, you may drive it directly to a repair shop, but avoid long trips and any situation where a sudden loss of power or instrumentation could be dangerous.

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.