OBD Guide

U0657

Lost Communication With Turbocharger/Supercharger Bypass Valve A Position Sensor

U0657 is an OBD-II diagnostic trouble code meaning: Lost Communication With Turbocharger/Supercharger Bypass Valve A Position Sensor. Common causes: bypass valve position sensor malfunction, open or short circuit in the sensor circuit. Estimated repair cost: $28–89.

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$28–89 (est.)

Symptoms

  • Reduced engine power
  • Check Engine Light Illuminates
  • Unstable engine operation
  • Acceleration problems
  • Turbocharging does not work

Causes

  • Bypass valve position sensor malfunction
  • Open or short circuit in the sensor circuit
  • Poor contact in the sensor connector
  • Wiring Harness Problems
  • Engine ECU malfunction

How to Fix

  1. Check the integrity of the sensor circuit
  2. Inspect connectors and contacts for corrosion or damage
  3. Check the resistance of the position sensor
  4. Scan the system for other errors
  5. If necessary, replace the bypass valve position sensor

Related codes

Error U0657 by Vehicle Brand

FAQ

What does the U0657 code mean?

U0657 is an OBD-II diagnostic trouble code that indicates: Lost Communication With Turbocharger/Supercharger Bypass Valve A Position Sensor

What causes a U0657 error code?

The most common causes of U0657 include: Bypass valve position sensor malfunction; Open or short circuit in the sensor circuit; Poor contact in the sensor connector; Wiring Harness Problems.

How do I fix a U0657 diagnostic trouble code?

To fix U0657: Check the integrity of the sensor circuit. Inspect connectors and contacts for corrosion or damage. Check the resistance of the position sensor. For a complete diagnosis, use an OBD-II scanner.

Is it safe to drive with U0657?

Limited driving only, diagnose soon

How much does it cost to fix U0657?

The estimated repair cost for U0657 is $28–89. Actual cost depends on your vehicle, location, and labor rates.

See also: Russian version · NationStat