Fault code P047D – exhaust pressure sensor “B” high input

Fault code P047D is called “Exhaust Pressure Sensor “B” High Input” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.

Technical description and explained code P047D

This Diagnostic Trouble Code (DTC) is a generic powertrain code. The P047D error is considered a generic code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly from model to model.

Fault code P047D – exhaust pressure sensor

Error code P047D OBD2 indicates that the incoming signal from the “B” exhaust pressure sensor does not match the inlet manifold pressure. This may be an electrical circuit fault.

This fault may be present at the same time as P047B. The main difference is that P047D is an electrical problem. And P047B can be the result of mechanical or electrical fault.

Usually it is recommended to start with fixing P047D (electrical) first, and then move on to P047B (electrical/mechanical). This way, if the problem is electrical related, the probability of repair is increased.

The troubleshooting steps may differ depending on the manufacturer, gasoline or diesel. As well as the type of exhaust pressure sensor and the color of the wires.

Symptoms of vehicle malfunctions

The main signal that an error P047D has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.

It can also be warning signs such as:

  1. Check engine control lamp on the control panel will light up (the code will be recorded in the ECM memory as a fault).
  2. Engine power drop.
  3. Exhaust pressure regulator may malfunction.

Fault P047D is considered serious, as there may be some problems with controllability and performance of the car. The fault itself is easily solved by replacing the faulty exhaust pressure sensor.

Factors that can cause this error code

The error code P047D can mean that one or more of the following problems have occurred:

  • Open circuit in signal line between exhaust pressure sensor and PCM.
  • Damage to the power supply circuit between the exhaust pressure sensor and PCM.
  • Short to earth in the signal circuit of the exhaust pressure sensor.
  • Faulty exhaust pressure sensor (internal short to ground).
  • In rare cases, transmission control module (PCM) may malfunction.

How to fix or reset OBD-2 code P047D

Some suggested steps for troubleshooting and fix the error code P047D:

  1. First, connect an OBD-II scanner to the vehicle’s onboard computer and read all stored data and error codes.
  2. Then clear the error codes from the PCM memory and test-drive the vehicle to see if error P047D appears again.
  3. If the error code appears again, confirm that there is a problem and continue diagnostics.

Diagnose and repair of problems

Locate the “B” exhaust pressure sensor on your vehicle. Disconnect the tube that connects the sensor to the exhaust manifold. If this is not possible, slip a small piece of wire through to remove any soot stuck inside.

If the tube is clean, inspect the connectors and wiring. Look for scuffs, exposed wires, burn spots, or melted plastic. Disconnect the connectors and carefully inspect the terminals inside the connectors.

Next, make sure the tubing that connects the turbocharger to the intake manifold is tight. Visually check all tubing connections around the turbocharger and intake manifold. Tighten all hose clamps.

If you have an error scanner, clear the diagnostic trouble codes from memory and see if code P047D returns. If it doesn’t, it’s probably a connection problem.

If the code returns, you will need to test the sensor and its associated circuits. Usually the exhaust pressure sensor has 3 wires. Use a digital multimeter to check the 5V power supply circuit going to the sensor.

If all is normal, check that the exhaust pressure sensor is securely grounded. Connect the test light, if it does not light up, this indicates a faulty circuit. If it lights up, jiggle the wiring harness going to the sensor to see if the check lamp flashes, indicating an intermittent connection.

If code P047D still comes up when you run all the tests, it probably indicates a faulty exhaust pressure sensor. But a failed PCM module also cannot be ruled out until the sensor is replaced.

On which vehicles does this problem occur most frequently

Fault code P047D can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:

  • Ford
  • Mercedes-Benz
  • Nissan
  • Renault (Duster)
  • Volkswagen

Fault code P047D can sometimes be found with other errors. The most common are the following: P047A, P047B, P047C, P047E.


Rate article
AutoNevod | Technical description of OBD-2 car faults and their solution
Add a comment