P024E

Charge Air Cooler Bypass Position Sensor A Circuit Low

P024E is a generic OBD-II powertrain diagnostic trouble code: Charge Air Cooler Bypass Position Sensor A Circuit Low. It is logged by the engine control unit when the powertrain monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
P024E
Group
Powertrain
System
Powertrain
Severity
Warning (MIL on, possible limp mode)
Need P024E disabled?
RaceTune permanently disables any OBD-II trouble code on supported ECUs — for motorsport, off-road, and export use.
→

What P024E means

P024E is stored when the ECM measures a lower-than-expected voltage on the Charge Air Cooler bypass position sensor signal circuit. In a typical potentiometer-style position sensor, the signal voltage tracks the physical position of the bypass valve and should remain within a defined window — usually around 0.5 V to 4.5 V. When the sensed voltage drops below the minimum calibrated threshold (often near 0.1–0.2 V), the ECM interprets this as a circuit low condition and sets P024E. This most commonly results from a short to ground somewhere in the signal wire, a failed sensor whose internal resistance has collapsed, or a poor ground reference causing the signal to read artificially low. Turbocharged vehicles relying on accurate bypass valve position feedback — such as Ford EcoBoost, GM turbo four-cylinders, and Toyota forced-induction models — are among those most frequently affected. Because a low-voltage reading renders the sensor signal unusable, the ECM may substitute a default valve position and illuminate the MIL. Engine performance may degrade noticeably until the circuit is restored to normal operating voltage.

Common causes

Most-frequently reported root causes when P024E is logged.

  • 1
    Short to ground on the sensor signal wire
  • 2
    Internally failed position sensor with collapsed output voltage
  • 3
    Broken or disconnected sensor ground wire creating a false low signal
  • 4
    Water ingress into the connector causing a low-resistance ground path
  • 5
    Chafed wiring harness contacting the chassis or engine block
  • 6
    Blown sensor supply fuse preventing reference voltage from reaching the sensor
  • 7
    ECM output driver fault incorrectly reading a low signal

Symptoms drivers notice

MIL (Check Engine Light) illuminated
Reduced engine power or engagement of limp mode
Poor throttle response on turbocharged vehicles
Engine hesitation or stumble, particularly on acceleration
Scan tool shows bypass position sensor voltage below 0.2 V at idle or under load
Possible companion codes for boost pressure or intake air temperature faults

How to diagnose P024E

A typical diagnostic flow when this code is present.

  1. 1
    Connect a scan tool and view live sensor voltage data; confirm voltage is consistently below the low threshold
  2. 2
    Inspect the sensor connector and wiring for signs of water intrusion, corrosion, or a ground short
  3. 3
    Disconnect the sensor connector and measure voltage at the harness-side reference pin — should be approximately 5 V
  4. 4
    Check continuity from the signal pin to chassis ground to identify any unintended short circuit
  5. 5
    Substitute a known-good sensor and clear codes to verify the fault follows the sensor versus the wiring
  6. 6
    Inspect fuse for sensor supply voltage and replace if open
  7. 7
    If wiring and sensor test normal, perform an ECM-level test or consult the manufacturer TSB for calibration issues

Related powertrain codes

Frequently asked questions

What voltage should the P024E sensor normally read?

Most charge air cooler bypass position sensors operate on a 5 V reference and produce a signal between approximately 0.5 V (fully closed) and 4.5 V (fully open). Readings persistently below 0.2 V indicate a circuit low condition.

Can a corroded connector alone cause P024E?

Yes. Heavy corrosion between the signal pin and adjacent ground pins inside the connector can create enough conductance to pull the signal voltage below threshold. Cleaning and re-terminating the connector often resolves the code without replacing the sensor.

How is P024E different from P024F?

P024E indicates the sensor voltage is abnormally low (usually a short to ground or open reference), while P024F indicates it is abnormally high (typically a short to supply or open signal/ground wire). Each points to opposite ends of a circuit fault.

Does P024E always cause limp mode?

Not universally — behavior varies by manufacturer calibration. Some vehicles substitute a fixed default valve position and continue running with limited power, while others impose a full limp mode to protect the engine from uncontrolled boost conditions.

Disabling P024E in software

RaceTune can permanently disable P024E — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent
The monitor is disabled in the ECU itself — not just cleared. It cannot return.
Tailored to your file
Each patch is matched to your specific software version — never a one-size-fits-all file.
Reversible
The original file is always preserved. Reflash the stock to return the ECU to factory state.

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

Got P024E in your scan?

Upload your ECU file — we'll identify the exact software version and confirm whether a disable is available for your car.

Upload your file