P2471: Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 4
The P2471 code indicates that the Engine Control Module (ECM) has detected a high voltage signal from the exhaust gas temperature (EGT) sensor located in Bank 1, Sensor 4 (typically downstream of the diesel particulate filter or catalytic converter). This sensor monitors exhaust temperature to protect components and optimize emissions. A high circuit voltage suggests an open circuit, short to power, or a faulty sensor. This can lead to incorrect temperature readings, potentially causing regeneration issues in diesel engines or catalyst damage.
1. Most Common Causes
- Faulty exhaust gas temperature sensor
- Open or shorted wiring in the sensor circuit
- Corroded or damaged connector
- ECM software or hardware issue
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced fuel efficiency
- Possible limp mode or reduced engine power
- Failed emissions test
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for related codes.
Step 2: Visually inspect the EGT sensor and wiring for damage, corrosion, or loose connections.
Step 3: Measure voltage at the sensor connector with the engine running; compare to manufacturer specifications (typically 0.5-4.5V).
Step 4: Test sensor resistance with a multimeter; replace if out of spec.
Step 5: If wiring and sensor are good, check for ECM issues or perform a software update.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as incorrect temperature readings can cause damage to the catalytic converter or DPF, leading to costly repairs.
How much does it cost to fix?▼
The cost typically ranges from $150 to $300, including parts (sensor $50-$150) and labor (1-2 hours at $100-$150 per hour).
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.