U0058 Code: High-Speed CAN Communication Bus Performance Problem
Short Description:
U0058 is a network Diagnostic Trouble Code (DTC) indicating that the High-Speed Controller Area Network (CAN) Bus is operating with abnormal communication performance. One or more control modules have detected unstable or degraded network communication.
What Does U0058 Mean?
The U0058 code indicates that communication quality on the High-Speed CAN Bus has fallen outside normal operating limits. Unlike a complete communication failure, this code usually points to reduced network performance caused by electrical noise, high circuit resistance, intermittent wiring faults, poor grounding, low system voltage, or a malfunctioning control module.
The High-Speed CAN Bus allows continuous communication between critical electronic modules such as the Engine Control Module (ECM), Transmission Control Module (TCM), ABS Module, Body Control Module (BCM), Electric Power Steering (EPS), Instrument Cluster, and many other controllers. A fault in this network may affect several vehicle systems simultaneously.
High-Speed CAN Bus Overview
The High-Speed CAN Bus is a two-wire differential communication network designed to transmit data rapidly while resisting electrical interference. CAN High (CAN-H) and CAN Low (CAN-L) carry opposite voltage signals, allowing reliable communication even in electrically noisy environments.
Damage to CAN wiring, loose connectors, poor ground connections, failed termination resistors, unstable battery voltage, or an internally faulty control module can reduce communication quality and trigger the U0058 diagnostic trouble code.
Common Symptoms
Vehicles affected by U0058 may exhibit one or more of the following symptoms.
| Symptom | Description |
|---|---|
| Check Engine Light | Communication fault has been detected. |
| ABS / ESC Warning | Brake or stability system warnings may appear. |
| Intermittent Communication | Control modules may randomly disconnect. |
| Electronic System Malfunctions | Multiple vehicle functions may operate incorrectly. |
Common Causes
The following conditions are the most common causes of the U0058 code.
| Cause | Explanation |
|---|---|
| Damaged CAN Wiring | Broken wires or excessive circuit resistance. |
| Loose or Corroded Connector | Poor terminal contact interrupts communication. |
| Weak Battery | Low voltage reduces network stability. |
| Poor Ground | Ground faults create unstable CAN signals. |
| Faulty Control Module | A defective module can disturb the entire CAN network. |
High-Speed CAN Bus Network Diagram
The simplified diagram below illustrates how major vehicle modules communicate through the High-Speed CAN Bus.
Diagnosis Procedure
Start by performing a complete network scan using a professional diagnostic scanner. Record all stored communication DTCs before clearing codes. Check battery voltage, charging system output, CAN wiring, connectors, ground circuits, and network resistance before replacing any electronic control module.
Step 1: Scan All Control Modules
Communication faults often affect multiple modules at the same time. Any module that is offline or intermittently unavailable can help identify the location of the network problem.
| Related Code | Description |
|---|---|
| U0100 | Lost Communication With ECM/PCM |
| U0121 | Lost Communication With ABS Module |
| U0140 | Lost Communication With BCM |
| U0155 | Lost Communication With Instrument Cluster |
Typical Live Data
The following values are typical references for most High-Speed CAN Bus systems. Always verify specifications for the vehicle being diagnosed.
| Parameter | Typical Value | Fault Indication |
|---|---|---|
| CAN High (CAN-H) | 2.5–3.5 V | Fixed Voltage / No Activity |
| CAN Low (CAN-L) | 2.5–1.5 V | Fixed Voltage / No Activity |
| Bus Resistance | ≈60 Ω | 0 Ω / 120 Ω / Open Circuit |
| Module Status | Online | Offline / Intermittent |
Oscilloscope Waveform Analysis
A dual-channel oscilloscope is the preferred tool for evaluating CAN Bus signal quality. CAN High and CAN Low should produce clean mirrored waveforms during normal communication.
Normal Signal
Distorted Signal
No Communication
Estimated Repair Cost
| Repair | Estimated Cost |
|---|---|
| Repair CAN Wiring | $50–300 |
| Replace Connector | $30–150 |
| Module Programming | $100–400 |
| Replace Control Module | $300–1,500+ |
Severity Level
Severity: High
U0058 can affect communication between major vehicle control modules, resulting in problems with engine management, transmission operation, ABS, steering assistance, and other electronic systems. Immediate diagnosis is recommended.
Common Repair Mistakes
Do not replace control modules before verifying battery condition, charging voltage, CAN Bus resistance, connector integrity, wiring continuity, and ground quality. Electrical faults are significantly more common than module failures.
Recommended Diagnostic Tools
Recommended tools include a professional full-system scan tool, digital multimeter, dual-channel oscilloscope, and manufacturer wiring diagrams to accurately diagnose High-Speed CAN Bus communication problems.
Frequently Asked Questions (FAQ)
Can I continue driving with the U0058 code?
The vehicle may still be drivable if the communication problem is intermittent. However, because U0058 affects the High-Speed CAN Bus, important systems such as the engine, transmission, ABS, steering, and body control modules may not operate correctly. The fault should be diagnosed and repaired as soon as possible.
Can a weak battery cause U0058?
Yes. A weak battery, unstable charging voltage, or poor electrical power supply can interfere with CAN Bus communication and trigger the U0058 diagnostic trouble code.
Can damaged CAN wiring trigger U0058?
Yes. Damaged wiring, short circuits, open circuits, loose terminals, corrosion, or excessive resistance in the CAN High or CAN Low circuits are among the most common causes of U0058.
What is the normal CAN Bus resistance?
With the ignition switched OFF, resistance measured between CAN High and CAN Low is typically about 60 Ω. Readings near 120 Ω, 0 Ω, or an open circuit usually indicate a CAN network fault. Always compare measurements with the manufacturer's specifications.
Can a faulty control module cause U0058?
Yes. An internally faulty control module can interfere with CAN Bus communication and create multiple communication-related DTCs. However, damaged wiring, poor ground connections, battery voltage problems, and connector corrosion remain much more common causes.
Conclusion
The U0058 diagnostic trouble code indicates degraded High-Speed CAN Bus communication rather than failure of a single sensor or actuator. Proper diagnosis should include checking battery voltage, charging system output, CAN Bus resistance, wiring continuity, connector condition, module power and ground circuits, live data, and oscilloscope waveforms. Following a systematic diagnostic procedure helps locate the root cause accurately while preventing unnecessary replacement of expensive control modules.
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