P2CED

Code

Generic P — Powertrain

Particulate Filter Pressure Sensor D Circuit High

Brand: Generic

Type: P — Powertrain

Views: UK: 24 EN: 37 RU: 21

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Page language: EN

Causes

Open or shorted wiring in the pressure sensor "D" signal circuit
Poor connector connection — corrosion, bent or pushed-out terminal
Faulty particulate filter pressure sensor (internal failure)
Short to B+ (voltage) on the signal wire
Failed sensor reference or ground circuit
PCM/ECM fault (rare)

Symptoms

Malfunction Indicator Lamp (MIL)/Check Engine Light illuminated
Reduced engine performance or limp mode on some vehicles
DPF warning messages, forced regen requests, or frequent regens
Poor fuel economy or rough running in severe cases
Diagnostic trouble codes related to exhaust/DPF control

What to check

Retrieve code and freeze-frame data with a scan tool; record live sensor value and reference voltage
Visually inspect sensor, connector, and wiring harness for damage, corrosion, or pin damage
Back-probe the signal, reference (Vref) and ground with ignition ON to measure voltages
Wiggle the harness and connector while watching live data for intermittent changes
Inspect pressure/vacuum hoses to/from the sensor for restriction, kinks, disconnects or collapsed lines
Check for related codes that may indicate reference or ground problems or DPF efficiency faults

Signal parameters

Vref (reference) typically ~5.0 V with key ON (acceptable range about 4.75–5.25 V)
Sensor signal at low/no differential pressure commonly ~0.5–1.5 V; under higher differential pressure up to ~4.5 V (manufacturer-specific span)
Circuit-high condition usually indicated by signal ≥ ~4.7–5.0 V or signal equal to reference or battery voltage
Circuit-open/short behavior: signal stuck near battery voltage indicates short-to-B+; signal stuck high near Vref indicates short-to-reference; signal near 0 V indicates short-to-ground

Diagnostic algorithm

Safety first: wear PPE and work on a cool vehicle when inspecting hot components.
Connect a scan tool and confirm P2CED is current or stored; record freeze-frame and live data for the pressure sensor D, Vref and ground. Note values at key ON and engine running.
Visually inspect the sensor, connector, and wiring harness for damage, corrosion, melted insulation, or rodent chew marks. Repair or secure any damaged sections.
Measure reference voltage at the sensor connector with ignition ON. If Vref is outside the expected range (approx. 4.75–5.25 V), trace and repair the reference supply circuit before replacing the sensor.
Back-probe the signal wire and measure the sensor output with key ON and engine running (if safe). If signal is high (≥4.7 V) while pressure is known low, suspect a short to voltage or failed sensor.
Check continuity between sensor ground and chassis ground; expected very low resistance. Repair poor ground connections.
If wiring looks intact but signal is high, disconnect the sensor and measure the signal wire voltage at the harness connector. If the harness signal still reads high with sensor disconnected, the fault is in the wiring/vehicle side (short to B+ or reference).
If harness signal goes to an expected open-circuit voltage or shows no short when sensor disconnected, bench-test or replace the sensor and re-check codes.
Inspect pressure hoses for restriction, pinches or blockages and ensure ports are not clogged with soot. Repair or replace lines as needed.
After repairs, clear codes and perform a road or engine test monitoring live data. Re-scan to confirm the code does not return.
If wiring and sensor check good but code persists, perform ECM/PCM diagnostics per manufacturer procedure — ECM fault is rare and should be confirmed before replacement.