Diesel Trouble Codes

P0471 — Exhaust Pressure Sensor A Circuit Range/Performance — 6.7 Cummins (EGR + DPF, pre-SCR)

Exhaust Pressure Sensor A Circuit Range/Performance

Updated October 15, 2026

What it means

The ECM has detected the exhaust pressure sensor A signal is outside the expected range or performance.1

Most likely causes

  1. Exhaust pressure sensor A (pre-DPF/EGR pressure sensor) electrical fault or out-of-range signal — Check sensor supply voltage, ground, and signal circuit for opens/shorts and connector corrosion; compare sensor voltage to spec at key-on and idle. A biased or stuck signal can set range/performance.1
  2. Exhaust pressure sensor A wiring harness chafing/damage from heat or vibration — Inspect harness routing near exhaust/DPF and EGR components for melted insulation, chafing, or poor pin contact that alters the signal.1
  3. Exhaust system restriction or abnormal pressure affecting sensor reading — A plugged DPF, NAC, or exhaust blockage can drive pressure outside the calibrated range, leading to a range/performance fault. Verify DPF differential pressure and inspect for restriction.1
  4. ECM calibration / reference voltage issue — If multiple sensor circuits show odd values, verify ECM reference voltage and grounds before replacing the sensor.1

How to diagnose

  1. Verify code and freeze frame; confirm P0471 is present and note engine conditions.
  2. Inspect exhaust pressure sensor A connector and wiring for heat damage, corrosion, or chafing; repair as needed.
  3. Check sensor supply voltage, ground, and signal voltage at key-on and idle against service specifications; look for out-of-range or stuck values.
  4. Compare exhaust pressure readings to expected values using a scan tool; check for plausibility with DPF differential pressure and engine load.
  5. Inspect exhaust system for restriction (DPF/NAC plugging, collapsed pipe) that could cause abnormal pressure; evaluate differential pressure data.
  6. If electrical tests pass, substitute a known-good exhaust pressure sensor A and re-evaluate.
  7. Clear codes and road test under varied load to confirm repair.

Common mistake to avoid

Cleaning or replacing the DPF before checking its pressure sensor and tubes. Cracked, melted, plugged or wet sensor tubes, or a failing sensor, can set DPF codes while the filter itself is fine. They are cheap to check; clear and verify them before touching the filter. Source: FleetRabbit — P2002 DPF efficiency code causes and fixes.

Parts and tools you may need

Tools you’ll need

Rough cost and difficulty

Likely repairPartsShop laborWho usually does it
ECM/PCM software update—0.5–1.5 hrsShop
Wiring or connector repair$10–$1001–4 hrsDIY with tools and a manual
Exhaust backpressure sensor$60–$2000.5–1.5 hrsEasy DIY
DPF professional cleaning (bake and blow)$300–$7001–3 hrsShop

Typical US independent-shop figures; labor runs about $120–$180 per hour (dealers charge more). Confirm the diagnosis before buying parts.

When to see a pro

If wiring faults are extensive, the exhaust system is heavily corroded, or the DPF shows high differential pressure indicating plugging, have a diesel technician evaluate for safe repair and emissions compliance.

Check for recalls

Recalls are tied to your truck’s VIN, so check yours directly: enter the VIN at NHTSA’s recall lookup. Open safety recalls are repaired free at a dealer.

Sources

  1. Curated DTC seed — 6.7 Cummins (EGR + DPF, pre-SCR) (curated) ↩︎ ↩︎ ↩︎ ↩︎ ↩︎

Repair videos: P0471 on the 6.7 Cummins '07.5–'12

Third-party videos, not ours — picked for this engine. Confirm anything against the factory service information for your truck.

Dodge Ram 6.7 Cummins diesel P0471 exhaust pressure sensor — MotorCity Mechanic · 251K views

HOW TO REPLACE EXHAUST PRESSURE SENSOR ON A 2010 - 2018 RAM 3500 6.7L CUMMINS — DimasCarTech · 40K views