P05AE

Brake Pedal Position Sensor A / B Correlation

P05AE is a generic OBD-II powertrain diagnostic trouble code: Brake Pedal Position Sensor A / B Correlation. 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
P05AE
Group
Powertrain
System
Powertrain
Severity
Warning (MIL on)
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What P05AE means

P05AE is stored when the ECM or brake control module detects a disagreement between brake pedal position sensor A and brake pedal position sensor B signals that exceeds a calibrated correlation tolerance. Modern vehicles often use two redundant brake pedal position sensors to ensure reliability in systems such as brake-by-wire, adaptive cruise control, collision avoidance, and engine torque reduction strategies.

A correlation fault means both sensors are individually within their electrical operating range, but their signals do not agree with each other within the expected tolerance. This can result from a mechanical issue such as a loose sensor mounting, a sensor that has shifted on the pedal bracket, an internal sensor failure producing a biased output, or wiring issues affecting one sensor more than the other.

Because brake pedal position data is safety-critical, the system may default to a conservative braking strategy or disable certain assisted driving features when this code is present. Full diagnosis requires monitoring both sensor signals simultaneously with a scan tool while the pedal is depressed through its full range.

Common causes

Most-frequently reported root causes when P05AE is logged.

  • 1
    One brake pedal position sensor producing a biased or offset signal.
  • 2
    Loose or improperly mounted brake pedal position sensor.
  • 3
    Mechanical wear or play in the brake pedal linkage affecting one sensor differently.
  • 4
    Wiring fault causing signal offset on one of the two sensor circuits.
  • 5
    Contamination or moisture inside one sensor connector.
  • 6
    Internal failure of one sensor while the other remains correct.
  • 7
    Incorrectly installed replacement sensor with wrong calibration offset.

Symptoms drivers notice

MIL and possibly brake warning light illuminated.
Adaptive cruise control or automatic emergency braking may be disabled.
Brake feel may be normal despite the stored fault.
Possible torque reduction hesitation if engine management uses brake pedal signal.
Instrument cluster warning message on some vehicles.

How to diagnose P05AE

A typical diagnostic flow when this code is present.

  1. 1
    Retrieve all DTCs from all modules and record freeze frame data.
  2. 2
    Use a scan tool to monitor both brake pedal position sensor A and B values simultaneously.
  3. 3
    Slowly depress and release the brake pedal through its full travel while watching both signals.
  4. 4
    Identify which sensor diverges from the expected correlation at which pedal position.
  5. 5
    Inspect both sensor connectors and wiring for corrosion, moisture, or damage.
  6. 6
    Check sensor mounting hardware to ensure both sensors are securely attached to the pedal bracket.
  7. 7
    Replace the sensor that shows inconsistent or offset readings after confirming wiring is intact.

Related powertrain codes

Frequently asked questions

Is P05AE a safety-critical fault?

It can be. Brake pedal position data feeds safety systems such as emergency braking and adaptive cruise control. These features may be disabled until the fault is resolved.

Can P05AE be caused by low brake fluid?

Low brake fluid affects braking hydraulics but does not directly cause a sensor correlation fault. However, a sinking pedal from low fluid could produce unusual pedal travel patterns that stress the sensor correlation check.

Will recalibrating the sensors fix P05AE?

If the sensor has physically shifted position, remounting and recalibrating the sensor may resolve the fault. If one sensor has failed internally, recalibration will not help and replacement is required.

Can I clear P05AE and hope it does not return?

If the fault is intermittent due to a connector issue, resolving the connector problem and clearing the code may work. A persistent fault will return and requires proper diagnosis.

Disabling P05AE in software

RaceTune can permanently disable P05AE — 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.

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