What it means
The module detects a high signal from the bank 1 sensor 4 exhaust gas temperature sensor circuit. The code identifies a circuit signal fault, not a confirmed high exhaust temperature.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Bank 1 sensor 4 measures exhaust gas temperature, and the module monitors its electrical signal. P2471 means that signal is high, which can result from an open circuit, a short to voltage, or a failed sensor; it does not confirm that the exhaust itself is too hot.
Common causes
Most likely first.
- Open or damaged sensor circuit
- Signal shorted to voltage
- Faulty sensor
Symptoms
- Check engine light on
- DPF or emissions warning light may come on
- Reduced power or limited regeneration may occur
- Increased fuel consumption
How to diagnose it
- Read freeze-frame data and related EGT codes to determine when the bank 1 sensor 4 signal went high.
- Compare the scan-tool reading from bank 1 sensor 4 with other temperature readings and the engine's operating state.
- Inspect the sensor connector and wiring for loose terminals, corrosion, broken wires, or insulation damage near hot exhaust parts.
- Test the circuit for an open or a short to voltage using the manufacturer's wiring diagram and procedure.
- Test bank 1 sensor 4 itself against the manufacturer's specification to determine whether it is producing an incorrect signal.
- Confirm the repaired signal responds plausibly as the exhaust warms.
Common fixes
- Repair an open or broken wire in the bank 1 sensor 4 circuit.
- Repair wiring that is shorted to voltage.
- Clean or replace loose or corroded connector terminals.
- Replace bank 1 sensor 4 if testing confirms it is faulty.
Can I keep driving?
If the vehicle has normal power, keep driving gentle and arrange diagnosis soon. Avoid heavy loads if the DPF warning appears or power drops, because the high signal can disrupt regeneration decisions and emissions-system protection.
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.