What it means
The code indicates an electrical fault in the exhaust gas temperature sensor circuit at Bank 1, Sensor 2. The code alone does not identify the fault type or the sensor’s exact location relative to the exhaust components.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
An exhaust gas temperature sensor measures temperature at Bank 1 Sensor 2 so the control module can manage and protect exhaust aftertreatment components. The module monitors the sensor circuit for an electrical fault, but this general code does not specify whether the signal is low, high, open, or shorted. P2031 sets when the Bank 1 Sensor 2 circuit fails its electrical checks.
Common causes
Most likely first.
- EGT sensor failed
- Wiring damaged by heat
Symptoms
- Check-engine light
- Possible reduced engine performance
- Possible emissions-control or exhaust-system warning
How to diagnose it
- Read freeze-frame data and live readings for Bank 1 Sensor 2 alongside other EGT sensors to see whether the fault is constant or occurs under particular conditions.
- Use vehicle service information to locate Bank 1 Sensor 2, then inspect its sensor body, connector, and heat-exposed harness for damage or melted insulation.
- With the exhaust cool, check that the connector is fully seated and its terminals are clean and secure.
- Test the Bank 1 Sensor 2 circuit for opens, shorts, and poor connections between the sensor and control module using the wiring diagram.
- Compare sensor resistance or signal behavior with the manufacturer's specification to determine whether the sensor or its wiring is faulty.
- Clear the code and confirm that Bank 1 Sensor 2 reports a plausible temperature as the exhaust warms.
Common fixes
- Secure or clean the Bank 1 Sensor 2 connector if it is loose or contaminated.
- Repair heat-damaged wiring in the Bank 1 Sensor 2 circuit.
- Replace the Bank 1 Sensor 2 EGT sensor if it fails the specified test.
- Repair an open or short in the sensor circuit.
Can I keep driving?
Driving may be possible, but exhaust temperature monitoring and emissions control may be affected, and some vehicles may reduce performance. Avoid heavy loads if performance is reduced and arrange diagnosis soon.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.