Exhaust Gas Temperature Sensor 1/2 Correlation Bank 2
The P20E5 code indicates that the Engine Control Module (ECM) has detected a correlation error between Exhaust Gas Temperature (EGT) Sensor 1 and Sensor 2 on Bank 2. These sensors monitor exhaust temperature before and after the diesel particulate filter (DPF) or selective catalytic reduction (SCR) system. A mismatch in readings suggests one sensor is faulty, wiring issues, or an exhaust leak. This can lead to incorrect regeneration cycles, reduced fuel economy, and potential damage to emissions components.
1. Most Common Causes
- Faulty or degraded Bank 2 EGT sensor 1 or 2
- Short, open, or high resistance in the EGT sensor circuit wiring or connectors
- Exhaust leak between EGT sensor 1 and sensor 2
- Excessive soot or ash buildup on the sensor tip
- Internal PCM failure (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced fuel economy
- Poor engine performance or hesitation
- Failed emissions test
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect EGT sensors and wiring for damage or corrosion.
Step 3: Compare live data from both sensors; check for erratic or out-of-range values.
Step 4: Test sensor resistance and voltage with a multimeter per manufacturer specs.
Step 5: Inspect for exhaust leaks near the sensors.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause improper DPF regeneration, leading to clogged filters and costly repairs.
How much does it cost to fix?▼
Replacing an EGT sensor typically costs $50-$150 for parts and labor, but diagnosis may add $50-$100.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.