P024C
Charge Air Cooler Bypass Position Sensor A Circuit.
- Generic
- Powertrain
- Generic code
- Medium severity
How this code is built
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 2
- AreaFuel and air metering (injector circuit)
- 4C
- FaultThe specific fault in that area
What it means
P024C is the generic code for a fault in the charge air cooler bypass position sensor 'A' circuit. The engine control unit monitors the signal from the sensor that reports the position of the charge air cooler bypass valve or flap. It sets the code when that signal is outside the expected range, is missing or erratic, or does not make sense for the commanded position. Not every engine has this system, and the layout varies by model and engine.
Symptoms
- Engine warning light on
- Reduced power or the engine going into limp mode
- Poor or uneven boost response
- Hesitation or lack of performance under load
- Higher than normal intake air temperatures or fuel consumption
- Possible additional boost or intake temperature codes stored
Possible causes
- Damaged, chafed or corroded wiring to the bypass position sensor (open circuit, short to earth or short to supply)likely
- Poor connection at the sensor or control unit connector (corrosion, bent or loose pins, water ingress)likely
- Faulty bypass position sensor or sensor built into the bypass actuatorlikely
- Bypass valve or flap seized, sooty or mechanically damaged so position does not match the commandpossible
- Faulty actuator or its drive circuitpossible
- Sensor reference supply or earth fault shared with other sensorspossible
- Fault within the engine control unitrare
How to diagnose
- Read all stored and pending codes and note the freeze frame data, including engine load, speed and temperatures; check for related boost, intake temperature or actuator codes.
- Check for any applicable technical service bulletins or software updates for the specific model and engine.
- Visually inspect the bypass valve, actuator, sensor, wiring and connectors for damage, heat damage, chafing, oil, moisture or corrosion.
- With the connector disconnected, check the sensor supply, reference voltage and earth against the manufacturer's wiring diagram for your model.
- Check the wiring between sensor and control unit for continuity, and for shorts to earth or supply.
- View live data for bypass position and command, and operate the actuator with a suitable bidirectional test if available to see whether the reading follows.
- Check the bypass flap moves freely through its full range and is not sticking, loose or carbon-clogged.
- Clear the code and road test to confirm whether it returns and under what conditions.
How to fix
- Repair or replace damaged wiring and secure any chafed sections.
- Clean, repair or replace corroded or loose connectors and terminals.
- Replace the bypass position sensor or the actuator assembly if the sensor is not supplied separately, following the manufacturer's procedure.
- Free or replace a seized or damaged bypass valve or flap, and correct the cause of any contamination.
- Repair a supply or earth fault affecting the sensor circuit.
- Update the control unit software only if an outdated calibration is a known cause for your model; replace the control unit only after all other causes are ruled out.
Can I keep driving?
The car can usually be driven carefully for a short time, but it may have reduced power and poor boost control. Get it diagnosed soon, as a stuck bypass can raise intake temperatures and affect engine performance.
Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.