Fuel and air

P024F — Charge Air Cooler Bypass Position Sensor A Circuit High

Severity: medium Drive with care, to a shop

What P024F means

The engine control module monitors a sensor that reports the position of the charge air cooler (intercooler) bypass valve. P024F sets when that signal stays above the expected range. This usually points to an open or short to power in the circuit or a failed sensor, so the ECM can no longer tell where the valve actually is.

Symptoms

  • Check Engine light on
  • Reduced power or limp mode
  • Poor fuel economy
  • Hissing or whistling near the turbo and boost piping
  • Rough idle or hesitation under load

Possible causes

  1. Failed charge air cooler bypass position sensor A
  2. Open, shorted or corroded wiring or connector
  3. Stuck bypass valve or faulty valve actuator
  4. Rarely, a faulty ECM

How to diagnose

  1. Scan for all codes and review freeze frame data for related boost faults
  2. Inspect the sensor harness and connector for chafing, moisture, corrosion and loose pins
  3. Compare the scan tool bypass position reading with the commanded position
  4. Check sensor reference voltage (typically 5 V) and ground at the connector per the factory wiring diagram
  5. Test the signal wire for opens and shorts to power back to the ECM
  6. Check that the bypass valve and actuator move freely without binding or carbon buildup
  7. If wiring and sensor test good, check for ECM software updates or a module fault

Common fixes

  • Replace the bypass position sensor A
  • Repair or replace damaged wiring and connectors
  • Clean or replace the bypass valve and actuator
  • Reflash or replace the ECM if confirmed faulty

Questions and answers

What does P024F mean?

The ECM detected a high voltage in the charge air cooler bypass position sensor A circuit. The cause is usually the sensor, its wiring or the valve actuator.

Can I drive with code P024F?

Usually yes, briefly and with care, but expect possible power loss or limp mode. Get it diagnosed soon to avoid stressing the turbo system.

Will clearing P024F fix it?

Clearing the code only helps temporarily. If the sensor, wiring or valve problem remains, the code will return, so find and fix the cause first.

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.