OBD-II · Engine and powertrain (P)
P2031
Exhaust gas temperature sensor circuit, bank 1 sensor 2
What it means
The computer sees an electrical fault in this sensor's circuit. Exhaust gas temperature (EGT) sensors protect the turbo and catalysts and let the engine computer control DPF regeneration. Which physical sensor is "sensor 2" depends on the car.
Symptoms
- engine warning light
- DPF regeneration may be blocked, leading later to a DPF warning
- possibly reduced power (limp mode)
- car may otherwise drive normally
Likely causes, most likely first
| No. | Cause |
|---|---|
| 01 | failed EGT sensor (heat cycling) |
| 02 | melted or corroded connector |
| 03 | wiring chafed or burnt near the exhaust or turbo |
| 04 | engine computer input fault (rare) |
What to check, step by step
- 01With the engine cold, read all EGT sensors in live data - they should all be close to outside temperature.
- 02Inspect the sensor connector and wiring near the turbo and exhaust for melting, chafing and corrosion.
- 03With the circuit isolated as specified, compare resistance with the specification for that exact sensor at the measured temperature. Compare other sensors only if they have the same electrical characteristics.
- 04Check wiring continuity back to the engine computer.
- 05Replace the sensor if faulty; they often seize, so use penetrating oil and remove with the exhaust warm.