Exhaust Pressure Sensor Circuit Low
The P0472 code indicates that the Engine Control Module (ECM) has detected a voltage signal from the exhaust back pressure sensor that is lower than the expected range. This sensor monitors exhaust pressure to optimize EGR flow and turbocharger operation. A low circuit condition can be caused by a faulty sensor, wiring issues, or exhaust leaks, potentially leading to reduced engine performance and increased emissions.
01. Most Common Causes
- Faulty exhaust pressure sensor
- Open or shorted wiring in sensor circuit
- Poor electrical connection at sensor
- Exhaust system leak before sensor
- Failed ECM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or sluggish acceleration
- Poor fuel economy
- Rough idle or hesitation
- Increased exhaust smoke
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and freeze frame data.
Step 2: Visually inspect the exhaust pressure sensor and wiring for damage or corrosion.
Step 3: Test sensor voltage and ground with a multimeter; compare to manufacturer specs.
Step 4: Check for exhaust leaks near the sensor using a smoke machine or soapy water.
Step 5: If sensor and wiring are okay, test the ECM output; replace sensor if necessary.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause reduced performance and potential damage to the EGR or turbo system. Short trips to a repair shop are acceptable.
How much does it cost to fix?▼
The typical repair cost ranges from $50 to $150 for a new sensor plus labor. Wiring repairs may add $50-$100.