P024E — Charge Air Cooler Bypass Position Sensor "A" Circuit Low

OBD2 code P024E flags a problem with the sensor and actuator circuits (charge air cooler bypass position sensor "A" circuit low). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, blown fuse feeding the circuit, open or shorted wiring in the circuit.

powertrain (engine/transmission)

Is it safe to drive?

Drive cautiously until the circuit is repaired P024E usually does not require an immediate shutdown, but the ECU may limit or default the charge air cooler bypass control. Avoid heavy acceleration until the sensor circuit has been tested and the code has been cleared.

Typical symptoms

The check-engine light illuminates with P024E stored in the powertrain control module.
Boost delivery may become inconsistent, especially during acceleration or when substantial engine torque is requested.
Hesitation, surge, or reduced engine performance can occur if the ECU places the bypass valve in a default operating mode.
Some vehicles continue to run normally, and P024E is detected only during an OBD2 scan.

Common causes

The charge air cooler bypass position sensor A has an internal failure that produces an abnormally low signal.
The sensor signal wire is shorted to ground, commonly from damaged insulation or a pinched harness.
Corrosion, water intrusion, or a loose terminal has created a low-resistance path in the sensor circuit.
A poor sensor ground or an incorrect sensor reference voltage causes P024E to be reported by the ECU.
The wiring was connected incorrectly or a previous repair damaged the connector pins or sensor wiring.

How to diagnose with an OBD scanner

Confirm P024E and monitor the circuit Use an OBD2 scanner with an ELM327 adapter or AIScanAuto to confirm P024E. If the vehicle supports enhanced data, compare the commanded bypass-valve position with the reported sensor A position while the engine is below and above idle.
Inspect the sensor and connector Locate the charge air cooler bypass position sensor A and examine its connector for green corrosion, water, bent pins, heat damage, and oil contamination. Check the harness near moving suspension or engine components for chafing.
Perform circuit checks Using the vehicle wiring diagram, back-probe the sensor connector and measure its reference voltage, ground voltage, and signal voltage. A signal held near ground points to a shorted wire or failed sensor; a low supply or poor ground indicates a wiring or connector problem.
Verify mechanical operation Confirm that the charge air cooler bypass valve moves through its commanded range without a seized actuator or damaged linkage. A valve that cannot move properly can prevent the ECU from obtaining a valid position signal.
Repair and verification test Repair the wiring or replace the faulty sensor or integrated valve assembly as testing indicates. Clear P024E with the scanner, operate the vehicle through several throttle cycles, and confirm that the code does not return.

Approximate repair cost

A typical independent-shop repair for P024E is approximately $180–$900 USD, depending on whether the fault is wiring, a separate sensor, or an integrated bypass-valve and sensor assembly. These figures are estimates and vary by region, labor rate, and parts availability.

Common questions

What exactly does P024E mean?

P024E means the ECU detected an abnormally low voltage from the charge air cooler bypass position sensor A circuit.

Can I continue driving with P024E stored?

You can usually drive cautiously, but boost control may be reduced or placed in a default mode, so the fault should be repaired promptly.

Is the wiring or the position sensor more likely to be faulty?

P024E can result from either one. Inspect and electrically test the wiring and connector before replacing the position sensor.

What should be checked after repairing P024E?

Clear the code with an OBD2 scanner, verify proper bypass-valve movement, and confirm that P024E remains absent through several throttle cycles.

When the engine control unit detects that the signal from the charge air cooler bypass position sensor "A" has dropped below its normal operating voltage, it stores OBD2 code P024E. This fault falls into the "circuit low" category, meaning the voltage on that specific circuit sits too close to ground — essentially the opposite of what the computer expects to see. The PCM does not set this code after a single bad reading. Instead, it runs multiple verification checks under specific driving conditions before illuminating the check engine light and recording the failure.

The charge air cooler bypass valve regulates airflow through the intercooler system. On turbocharged or supercharged engines, the bypass valve allows pressurized air to either flow through the intercooler for cooling or route around it during certain operating conditions. The position sensor "A" tells the control module exactly where that valve is at any given moment — open, closed, or somewhere in between. When P024E appears, the PCM can no longer trust the position data from this sensor, so it falls back to default strategies that may reduce boost performance or activate limp-home mode depending on your specific vehicle platform.

Why would the voltage drop? The most common culprits are a short to ground somewhere in the wiring harness, a failed sensor pulling the signal low on its own, missing supply voltage reaching the component, or a poor ground connection at the sensor itself. Corrosion at the connector, a blown fuse feeding that circuit, or even a problem inside the control module driver can also produce the same result. The freeze frame data stored alongside P024E shows engine load, RPM, coolant temperature, and vehicle speed at the moment of failure — use those numbers to recreate the fault condition during testing.

Common Symptoms of P024E

Check Engine Light illuminated on the dashboard
The charge air cooler bypass system operates intermittently or stops functioning entirely
Noticeable increase in fuel consumption under normal driving
Reduced engine performance or hesitation under boost
Limp-home mode activated, limiting power output
In rare cases, abnormal surging or stuttering during acceleration

What Causes P024E

Signal wire shorted to ground due to chafed or damaged insulation
Failed charge air cooler bypass position sensor "A" internally pulling the signal low
Missing or insufficient supply voltage reaching the sensor connector
Corroded, loose, or physically damaged electrical connector at the sensor
Control module driver circuit failure within the PCM itself
Blown fuse protecting the affected sensor circuit
Poor ground connection at the sensor mounting point or ground splice
Open circuit or secondary short somewhere in the wiring harness

How to Diagnose P024E

Connect an OBD2 scanner and confirm P024E is present in the stored codes. Save the freeze frame data immediately — this snapshot tells you exactly what engine conditions triggered the fault and makes it easier to reproduce the problem during your diagnosis.
Check for any additional diagnostic trouble codes. Related codes often point to the underlying cause, such as power supply issues or communication failures. Also search for technical service bulletins (TSB) specific to your vehicle make, model, and model year — manufacturers sometimes release software updates or known-fix documentation for persistent P0xxx codes.
Perform a thorough visual inspection of the wiring harness and connectors associated with the charge air cooler bypass position sensor "A". Look for cracked insulation, rubbed-through wires touching metal, water intrusion, corrosion buildup, or pins that are bent, pushed out, or making poor contact.
Test for supply voltage at the sensor connector first — most position sensors require a 5-volt reference from the PCM. Then check ground circuit continuity. Finally, measure resistance from the signal wire to ground at the harness side; a reading near zero ohms confirms a direct short to ground in the wiring.
Verify proper signal voltage at the component connector with the sensor installed and the system powered up. Compare your readings to manufacturer specifications. Wiggle-test the harness while monitoring live data — any signal dropouts or fluctuations point to broken wires inside the insulation.
If the harness and connectors check out completely, swap in a known-good charge air cooler bypass position sensor to rule out an internal component failure. Check fuses and relay circuits while you are at it.
Clear the code, complete a full drive cycle including the specific conditions from your freeze frame data, and verify that P024E does not return.

Repair Options and Costs

The fix depends entirely on which part failed. Always address the cheapest and most common causes before replacing expensive components.

Replace the faulty charge air cooler bypass position sensor or actuator: $150–$500
Repair damaged wiring or connector terminals: $80–$250
Control module diagnosis and repair or replacement: $300–$1,000

Total Cost to Fix P024E

Parts and labor at independent shop rates (USD):

The sensor or actuator replacement runs $150 to $500 depending on the part cost and local labor rates. Wiring repairs or connector replacement typically fall between $80 and $250. Control module work is the most expensive scenario, ranging from $300 to $1,000 when you factor in diagnosis time, module repair or replacement, and programming if required.

Most P024E repairs end up costing between $80 and $500 when the problem turns out to be wiring or a bad sensor. Spending time on an accurate diagnosis before buying parts almost always saves money — the control module is rarely the culprit, but it should be ruled out last.

Can You Drive with P024E?

P024E carries a short-term drivability rating. In most cases, the vehicle remains operational but with reduced performance or a disabled boost-related system. If the car enters limp-home mode, you lose significant power. Do not ignore symptoms like stalling, hard starting, or warning lights related to braking or steering assist — those situations require immediate professional attention.