Error code

OBD2 U0401

OBD2U0401
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Invalid Data Received From ECM/PCM.

Severity

highDriving may be unsafe due to potential issues with ABS/Traction Control/Stability Control systems.

Summary

U0401 indicates invalid data received by the ECM/PCM, suggesting a communication issue within the CAN bus system.

Symptoms

  • Varying degrees of power loss
  • Misfire-like symptoms on some applications
  • Transmission entering fail-safe or limp mode
  • ABS/Traction Control/Stability Control systems deactivation

Common Causes

  • Damaged, burnt, shorted, disconnected, or corroded wiring and/or connectors
  • Abnormal system voltages
  • Defective engine and driveability sensors (on some applications)
  • One or more defective control modules

Diagnosis

  1. Record all fault codes and freeze frame data.
  2. Perform a thorough visual inspection of wiring and connectors.
  3. Check resistance, ground integrity, continuity, and reference voltage on associated wiring.
  4. Clear codes after repairs and operate the vehicle for at least one drive cycle.

Fixes

  • Replace sections of damaged or corroded wiring.
  • Replace individual wiring harnesses as needed.
  • Replace failed control modules, potentially requiring reprogramming.

FAQ

Can I drive with U0401?

Driving may be unsafe due to potential issues with ABS/Traction Control/Stability Control systems.

How difficult is it to diagnose and fix U0401?

Diagnosing and fixing U0401 often requires advanced diagnostic equipment and skills. DIY repairs may be possible but are generally challenging without proper tools and knowledge.

View source

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.

More OBD2 codes

All OBD2 codes →Search more codes →