P047C code meaning
Exhaust Pressure Sensor B Circuit Low
Powertrain system Generic code P04xx codes Check engine light
What P047C means
The exhaust pressure sensor measures the pressure ahead of the turbine or in the manifold (Ford: turbine upstream pressure, Cummins: exhaust manifold pressure, older Ford diesels: EBP). The module uses it to calculate EGR flow, to control the variable turbine and engine braking, and to protect against overpressure. No manufacturer document available to us uses sensor B – it would be a second sensor, for example on bank 2 of a twin-turbo engine; the description mirrors sensor A. P047C means the signal voltage of sensor B is below its limit (for sensor A Ford uses 0.1 V or 0.21 V).
P047C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P047C
- Check engine light on
- EGR and turbo control on a substitute value, possibly reduced power
- Exhaust brake or warm-up flap without function
Common causes of P047C
- Most likelySignal wire shorted to ground
- Possible5 V reference open or shorted (often shared with other sensors)
- PossibleSensor faulty internally
- PossibleConnector damaged by heat or corrosion
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Exhaust pressure sensor bSensor wiringEngine control module
What each part of P047C means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 7C | The exact fault in that area. |
What to do next
- Note P047C and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P047C
What does P047C mean?
P047C means "Exhaust Pressure Sensor B Circuit Low". The exhaust pressure sensor measures the pressure ahead of the turbine or in the manifold (Ford: turbine upstream pressure, Cummins: exhaust manifold pressure, older Ford diesels: EBP). It is a generic code, so it means the same on every make.
Is it safe to drive with P047C?
Drive gently and only to a workshop. With P047C the car can go into limp mode (reduced power) to protect itself.
Will P047C fail an emissions test?
Yes, it can. P047C is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P047C to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P047C clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.