P246A: Exhaust Gas Temperature Sensor Circuit Intermittent/Erratic Bank 2 Sensor 3
The P246A code indicates that the Engine Control Module (ECM) has detected an intermittent or erratic signal from the exhaust gas temperature (EGT) sensor located after the diesel particulate filter (DPF) on Bank 2, Sensor 3. This sensor monitors exhaust temperature to protect the DPF and optimize regeneration. An intermittent signal can be caused by wiring issues, connector corrosion, or a failing sensor. If left unresolved, it may lead to improper DPF regeneration, reduced fuel economy, and potential damage to the exhaust system.
1. Most Common Causes
- Faulty exhaust gas temperature sensor
- Damaged or corroded wiring/connectors
- Intermittent short or open in the sensor circuit
- ECM software issues (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine performance or fuel economy
- DPF regeneration issues (frequent or incomplete regeneration)
- Possible limp mode activation
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data to confirm P246A and check for related codes.
Step 2: Visually inspect the EGT sensor (Bank 2, Sensor 3) wiring and connector for damage, corrosion, or loose connections.
Step 3: Use a multimeter to test sensor resistance and compare to manufacturer specifications; also check for continuity and shorts in the wiring harness.
Step 4: If wiring is intact, replace the EGT sensor and clear the code; test drive to verify repair.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with this code, as it can lead to improper DPF regeneration and potential exhaust system damage. Short trips to a repair shop are acceptable.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for the sensor part, plus labor if you have a mechanic replace it. DIY replacement can save labor costs.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.