A faulty charge air cooler bypass position sensor that has drifted or failed internally; Damaged, corroded, or chafed wiring in the sensor signal or reference voltage circuit; A sticking or mechanically binding bypass valve actuator that prevents the sensor from reaching commanded positions; Poor electrical connection at the sensor harness connector due to water intrusion or terminal fretting; A failed or leaking vacuum or electronic actuator that moves the bypass valve, causing a position mismatch; An intake air restriction or boost leak that changes the expected bypass position under load; A software calibration issue or a faulty powertrain control module, though this is the least likely cause

DTC codes / P02xx · Fuel and air metering (injector circuits) / P024D

P024DCharge Air Cooler Bypass Position Sensor A Circuit Range/Performance

P024D indicates that the powertrain control module has detected an out-of-range or performance fault in the signal circuit for the charge air cooler bypass position sensor on bank A. The sensor reports the physical position of the bypass valve that routes intake air around or through the charge air cooler, and the computer compares that signal against expected values under current operating conditions. When the voltage or rationality check falls outside the calibrated window, the module stores this code and may command a default actuator position.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Illumination of the check engine light, often with no other noticeable symptoms besides the warning light
Reduced engine power or a limp-home mode triggered by the powertrain control module
Poor throttle response or hesitation during acceleration when the bypass valve fails to move as commanded
Decreased fuel economy or altered turbocharger boost behavior because charge air temperature control is compromised
Intermittent rough running or surging under light load if the bypass valve sticks partway open
A stored pending code or freeze-frame data showing the fault occurred during a specific boost and temperature condition

Common causes, most likely first

A faulty charge air cooler bypass position sensor that has drifted or failed internally
Damaged, corroded, or chafed wiring in the sensor signal or reference voltage circuit
A sticking or mechanically binding bypass valve actuator that prevents the sensor from reaching commanded positions
Poor electrical connection at the sensor harness connector due to water intrusion or terminal fretting
A failed or leaking vacuum or electronic actuator that moves the bypass valve, causing a position mismatch
An intake air restriction or boost leak that changes the expected bypass position under load
A software calibration issue or a faulty powertrain control module, though this is the least likely cause

How to diagnose and fix it

Connect a scan tool and record the freeze-frame data and any related codes to understand the exact conditions when P024D set
Visually inspect the bypass position sensor, its connector, and the actuator linkage for obvious damage, corrosion, or binding
Back-probe the sensor connector and check reference voltage, ground, and signal voltage against the manufacturer's specification
Command the bypass valve through its full range with the scan tool and watch the sensor signal for smooth, consistent movement
Check for intake leaks or restrictions between the turbocharger, charge air cooler, and throttle body that could skew expected position values
If the sensor signal is erratic or out of range, replace the charge air cooler bypass position sensor and clear the code
After repair, perform a road test with the scan tool monitoring bypass position and confirm the code does not return

What the bypass sensor signal really tells you

A common misdiagnosis is replacing the bypass valve actuator when the actual fault is a worn sensor signal track that only drops out at a specific temperature or vibration frequency.
The powertrain control module often sets P024D only after the bypass valve fails a commanded movement test, so a sensor that reads correctly at idle can still be faulty under boost.
Charge air cooler bypass position sensors on some engines share a reference voltage with other sensors, so a short in a neighbouring circuit can pull down the signal and set this code.
A sticking bypass valve can cause the sensor to report a plausible position that does not match the commanded position, which sets a range or performance code rather than a circuit low or high code.
After any repair, the bypass valve may need a relearn or calibration procedure through the scan tool before the monitor will pass and the code will stay cleared.

Can I keep driving with P024D?

You can usually drive the vehicle to a repair shop, but avoid heavy acceleration and sustained high-load driving because the bypass valve may be stuck in a default position that affects charge air cooling and turbocharger efficiency. If the engine enters limp mode or you notice severe power loss, have the vehicle towed rather than continuing to drive.

Tools that help

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Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.