P0473
UniversalExhaust Pressure Sensor High
The engine computer has detected a high signal from the exhaust pressure sensor circuit. The sensor reports exhaust pressure so the computer can monitor engine operation; a high signal may come from an electrical problem, a sensor issue, or genuinely high exhaust pressure. The code does not by itself prove the sensor needs replacement. The warning light may be the only noticeable effect, though performance or emissions operation can be affected.
⚠️ Before You Begin (Safety First)
Avoid touching the exhaust or sensor while hot. If the vehicle has severe power loss, unusual exhaust fumes or a suspected exhaust leak, stop driving when safe and arrange inspection. Otherwise, have the fault diagnosed promptly, especially if warning lights or drivability problems worsen.
Common Symptoms
- The check-engine light may turn on, with no obvious change in how the vehicle runs.
- The engine computer may receive misleading exhaust-pressure information, which can affect engine management or emissions operation.
- Some vehicles may have reduced performance or other drivability changes if the detected condition affects control strategies.
Common Causes
- A fault inside the exhaust pressure sensor may produce an abnormally high signal.
- Damaged wiring or a poor connection may cause the signal circuit to read high.
- A circuit short to a voltage source may produce a high sensor signal.
- A blocked pressure passage or genuinely high exhaust pressure may contribute to an abnormal reading; vehicle-specific testing is needed to distinguish these from an electrical fault.
Diagnostic Steps
- Check for other warning lights and note any changes in performance. This helps establish whether the code is accompanied by a broader problem.
- With the vehicle off and the exhaust fully cool, visually inspect the accessible sensor wiring and connector for damage, looseness or contamination. Do not pull on wires or touch hot exhaust components.
- If a suitable scan tool is available, record related codes and observe the exhaust-pressure reading without assuming a particular value is correct. Compare it with vehicle-specific service information.
- If the code returns or the wiring is not clearly damaged, arrange vehicle-specific electrical and pressure-passage testing before replacing parts.
When to Call a Professional
Confirm the code and review relevant scan data before replacing parts. Using the vehicle-specific wiring diagram, check the sensor circuit's power, ground and signal, and inspect the connector and harness. Compare sensor readings with expected behavior under the applicable test conditions, then check the sensor pressure passage and exhaust system for blockage or other causes of genuinely high pressure. Exact procedures depend on model, year and engine.
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Commonly Asked Questions
Does P0473 prove the exhaust pressure sensor is bad?
No. It means the computer detected a high signal in the exhaust pressure sensor circuit. Wiring, connections, the sensor, a blocked passage or genuinely high exhaust pressure may need to be considered.
Can I keep driving with P0473?
If the vehicle runs normally and there are no other warnings, arrange diagnosis promptly and monitor for changes. Stop driving when safe if there is severe power loss, unusual exhaust fumes or a suspected exhaust leak.
What does the exhaust pressure sensor do?
It reports exhaust pressure to the engine computer, which uses the information to monitor engine operation. The specific control strategy varies by vehicle.
Why check wiring before replacing the sensor?
A damaged connection or a short to voltage can create a high signal even when the sensor itself is functional. Circuit tests help identify the cause before parts are replaced.
Browse Available Code Guides
Previous and next available guides in database record order, across makes. Adjacent entries may share a code number and do not necessarily describe related faults.