P0473
Exhaust Pressure Sensor A Circuit High
Exhaust / emissions control
Generic OBD-II
Medium
What it means
P0473 means the ECM has read an abnormally high signal from exhaust pressure sensor "A", which monitors back-pressure in the exhaust (often part of the EGR or diesel DPF system). The engine still starts, but the false-high reading can trigger reduced power and, on diesels, interfere with soot-filter regeneration, so it's worth addressing before long drives.
Medium
Can I keep driving? Usually drivable, but the engine may drop into reduced-power mode and diesel DPF/EGR functions can be affected, so repair it soon.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced power or limp mode (common on diesels)
- Decreased fuel efficiency
- Rough running under load
Common causes
Most likely first
- Faulty exhaust back-pressure sensorLikely
- Signal wire shorted high or reference/ground fault in the circuitCommon
- Loose or corroded sensor connectorCommon
- Clogged or damaged sensor pressure tube (carbon/soot)Less often
- Rarely, a failed ECMLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and inspect the exhaust pressure sensor and its pressure tube for soot blockage or damage.
- Check the connector and wiring for a short-to-voltage or open on the signal line.
- Compare the sensor's reading to actual/known pressure with a scan tool; replace the sensor if stuck high.
- Clear carbon from the sensor port or tube if blocked, then clear the code and re-test.
FAQ
Quick answers
Is it safe to drive with P0473?+
Short trips are usually fine, but many vehicles cut power to protect the engine, and on diesels it can disrupt DPF regeneration — fix it promptly.
Can I just clear P0473?+
It will return once the ECM reads the high signal again unless the sensor, wiring, or blocked tube is repaired.
Related codes
Often seen with P0473
Read & clear P0473 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX