Fuel and air

P2571 — Turbo Boost Control Position Sensor Circuit High (Alternate)

Severity: medium Drive with care, to a shop

What P2571 means

The engine control module tracks the position of the variable geometry turbo vanes or actuator through a position sensor. P2571 sets when the voltage on the alternate channel of that sensor stays above the expected range. This usually points to an open circuit, a short to power, or a failing sensor or actuator, so the ECM cannot control boost accurately.

Symptoms

  • Check engine light on
  • Reduced boost and loss of power
  • Sluggish acceleration, especially under load
  • Limp mode
  • Higher fuel use or smoky exhaust in severe cases

Possible causes

  1. Open circuit in the position sensor signal wire
  2. Failed position sensor or turbo actuator
  3. Signal wire shorted to voltage
  4. Damaged wiring harness or connector
  5. Poor connection or corroded terminals
  6. Faulty driver circuit inside the ECM

How to diagnose

  1. Scan all codes and freeze frame data, and look for other boost-related codes
  2. Inspect the sensor/actuator harness and connector for chafing, heat damage and corrosion
  3. Check supply voltage and ground at the sensor connector
  4. Measure the sensor signal with a meter or scan tool and compare it to the ECM command
  5. Test the signal wire for opens and shorts to power
  6. Check the turbo vane mechanism for sticking or carbon buildup
  7. If wiring is good, test the sensor and actuator, then consider the ECM

Common fixes

  • Repair damaged wiring or replace the connector
  • Clean the terminals and remove corrosion
  • Replace the position sensor or turbo actuator
  • Clean or replace a stuck VGT mechanism
  • Diagnose and repair or replace the ECM if the driver is faulty

Questions and answers

What does P2571 mean?

The ECM is reading a too-high signal from the alternate channel of the turbo boost control position sensor. The cause is usually wiring, a connector or the sensor itself.

Can I drive with P2571?

For a short time and with care, yes, but expect reduced power. Get it diagnosed soon to avoid turbo damage.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.