P2455

Particulate Filter Pressure Sensor A Circuit High

P2455 is a generic OBD-II powertrain diagnostic trouble code: Particulate Filter Pressure Sensor A Circuit High. It is logged by the engine control unit when the dpf monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code
P2455
Group
Powertrain
System
DPF
Severity
Warning (MIL on, possible limp mode)
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What P2455 means

P2455 is a generic SAE J2012 powertrain code that the ECM/PCM sets when the signal voltage from Diesel Particulate Filter (DPF) Differential Pressure Sensor A rises above the maximum calibrated threshold for longer than the manufacturer-defined plausibility window. The sensor measures the pressure drop across the DPF substrate to estimate soot load and trigger active or passive regeneration. A 'Circuit High' condition means the ECM is reading a voltage that is too high relative to what is physically possible given current engine operating conditions — this is the opposite failure polarity of P2454 (Circuit Low). Common electrical causes include a short-to-battery-voltage on the signal wire, an open or high-resistance sensor ground/reference-ground path, a missing or damaged sensor 5 V reference return, or an internally failed sensor that has gone rail-high. Until the fault is cleared and confirmed repaired, the ECM cannot accurately calculate DPF soot loading, which disables or degrades active regeneration control.

Common causes

Most-frequently reported root causes when P2455 is logged.

  • 1
    Short circuit between the DPF pressure sensor signal wire and a voltage source (battery positive or switched supply)
  • 2
    Open circuit or high resistance on the sensor ground wire or the 5 V reference return wire
  • 3
    Faulty DPF differential pressure sensor (internal failure with output stuck at or near supply voltage)
  • 4
    Damaged, corroded, or water-ingressed wiring harness connector at the DPF pressure sensor
  • 5
    Chafed or pinched wiring between the sensor and ECM that contacts a live circuit
  • 6
    ECM connector pin corrosion or back-out causing loss of the low-side reference
  • 7
    Failed or incorrectly installed aftermarket DPF pressure sensor with incompatible output range

Symptoms drivers notice

MIL (Check Engine light) illuminated
DPF warning light or regeneration inhibit indicator on
Reduced or absent DPF regeneration cycles — soot load may increase over time
Possible power reduction or limp-home mode on vehicles with strict DPF emissions enforcement
DPF pressure sensor PID reading implausibly high or pegged at maximum in live data
No immediately noticeable driveability change in early stages on vehicles without emissions limp-home

How to diagnose P2455

A typical diagnostic flow when this code is present.

  1. 1
    Retrieve all stored and pending DTCs; note whether companion codes P2452, P2453, or P2454 are also present
  2. 2
    Check live data for the DPF pressure sensor signal value — a reading pegged at or near the sensor supply voltage confirms the circuit-high condition
  3. 3
    Inspect the DPF pressure sensor, its connector, and the hose connections for physical damage, corrosion, moisture intrusion, or kinked/blocked pressure hoses
  4. 4
    Disconnect the sensor and observe the signal voltage at the ECM-side connector harness; if voltage remains high with sensor unplugged, the fault is in the wiring or ECM
  5. 5
    With sensor disconnected, check resistance from the signal wire to all voltage sources to identify any short-to-voltage path
  6. 6
    Verify sensor supply voltage and ground integrity at the sensor connector with DVOM
  7. 7
    If wiring checks out clean, substitute a known-good OEM-equivalent DPF differential pressure sensor and retest

Vehicles where we've handled P2455

Platforms in our catalogue with confirmed P2455 coverage.

VW TOURAN 20D
BMW 320D
2016

Related powertrain codes

Frequently asked questions

Can I drive with P2455 active?

Short term most vehicles remain driveable, but it is not advisable. Without accurate pressure data, regeneration may not trigger at the right time, allowing soot to accumulate. A heavily loaded DPF that misses regeneration cycles can become permanently blocked.

What is the difference between P2454 (Circuit Low) and P2455 (Circuit High)?

Both indicate an electrical fault on the same sensor circuit, but in opposite directions. P2454 means the signal voltage is below the minimum expected range (typically a short-to-ground or open signal wire), while P2455 means the voltage is above the maximum expected range (typically a short-to-voltage or open ground/reference-return).

Will replacing the DPF pressure sensor always fix P2455?

Not necessarily. Because the code is triggered by an out-of-range voltage, the fault is just as likely to be a wiring problem — particularly a short-to-voltage on the signal line or an open sensor ground — as a failed sensor. Always check the wiring and connector before condemning the sensor.

Does P2455 affect the DPF itself, or just the sensor?

P2455 is a sensor circuit fault, not a DPF substrate fault. The DPF itself may be perfectly fine. However, if the fault is left unresolved long enough that regeneration cannot occur, secondary DPF damage can result from accumulated soot.

Disabling P2455 in software

RaceTune can permanently disable P2455 — 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.

ECUs with a P2455 disable in our catalogue

Confirmed coverage from our recipe database — we support many more families. Upload your file and our identifier will match it automatically.

  • Bosch EDC16C31 verified 1 software version
  • Bosch EDC17C50 verified 1 software version
  • Bosch EDC17C60 verified 1 software version
  • Bosch EDC17C74 verified 1 software version
  • Bosch EDC17CP09 verified 1 software version

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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