Guide To P047B OBD Error Code Solutions

<<See All OBD Codes

This trouble code is generic, which would mean that it can apply to all the vehicles which are equipped with the OBD-II or the vehicles which are made since 1996 up to the present. The specifications on the definition, the troubleshooting steps as well as repairs can always vary from one vehicle make to another. This can happen because of a lot of reasons and the mechanic should diagnose the specific cause for this code.

The trouble code P047B can be defined as Exhaust Pressure Sensor B Range/Performance.

The exhaust back pressure sensor produces a linear analog voltage signal which indicates pressure when a 5-volt reference signal is supplied to it from the engine control module. It is a variable capacitance sensor. The main function of the EBP sensor is to measure exhaust back pressure so that the exhaust back pressure regulator can be controlled by the engine control module as per the requirement.

What causes this problem with the Exhaust Pressure Sensor B Range/Performance?

• The tube from the exhaust manifold to the pressure sensor might have blockage
• Issue of exhaust gas recirculation system / air inlet / charge air leaks
• Some faults in the exhaust gas pressure sensor
• The powertrain control module might have been defective
• Defaults in the exhaust back pressure sensor 'B'
• There might be open or shorted exhaust back pressure sensor 'B' harness
• Exhaust Back Pressure Sensor 'B' circuit might have bad electrical connection

1. EGR Valve Gasket - A faulty EGR Valve Gasket can be troublesome. You can always rely on us as we have best auto parts for our customers.
2. Turbocharger - If everything is alright with PCM, then there is surely some defect in Turbocharger. Get it replaced before the situation gets worse.
3. Exhaust Manifold - P047B code can display due to some flaws in the Exhaust Manifold. So it is very important to replace the Exhaust Manifold with us at equitable prices.
4. Supercharger - Do you remember when was the last time you got your car Supercharger checked up? A defective Supercharger can cause a lot of issues like displaying P047B code.
5. Manifold Absolute Pressure Sensor - Are there some faults in your Manifold Absolute Pressure Sensor? Don’t waste time and get them replaced or else P047B code can turn up.
6. Powertrain Control Module - Everything is fine with Supercharger and still P047B code triggering? Then you must get your Powertrain Control Module checked.
7. Fuel Pressure Sensor - There can be some issues with the Fuel Pressure Sensor due to which you may see P047B code appearing over and over again. Visit us to buy best quality Fuel Pressure Sensor online.

There could be countless symptoms which that would accompany with this fault code. Willing to know some common symptoms of OBD Trouble Code P047B? Your wish is our demand. Have a look at them below:

Common Symptoms

• Appearance of the check engine light
• There can be a decrease of power
• Unable to perform manual regeneration – burn off the soot out of the particulate filter. Looks like a catalytic converter but has temp sensors and pressure sensor probes inserted into it
• If unable to perform regeneration, eventually may become a crank-no start

Looking out for some ways with the help of which you can correct this fault code? Then you have arrived at the correct place. We are here to help you out, so you must check out the steps mentioned below as follows:

• If there is blockage in the tube from the exhaust manifold to the pressure sensor, then it should be corrected
• Replace or repair the exhaust gas recirculation system
• Make sure to repair the faulty exhaust gas pressure sensor
• The defective powertrain control module should be replaced
• Restore the quirky exhaust back pressure sensor 'B'

Don’t get tensed if you are still facing any of these issues as we care for our customers and that’s why we offer a good range of harness, manifold pressure, tire pressure gauge, oil pressure sensor, turbo kit and a lot more. We are sure that now all your issues would be resolved.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P047B code to be stored:

You must always start with a technical service bulletin search for your particular vehicle. The vehicle manufacturer may have a PCM flash/reprogram to cover this issue, and it pays to check on this before you find you’ve gone down a long/wrong path. The next step would be to locate the exhaust pressure sensor on your particular vehicle. Once located, disconnect the tube that connects the sensor to the exhaust manifold. Attempt to blow through it. If you are not able to do that, try to run a small piece of wire through it to dislodge the carbon that is trapped inside, causing the fault code you are encountering. If the tube is clear and free, then you must visually inspect the connectors and wiring.

Look for chafing, rubbing, bare wires, burn spots or melted plastic. The connectors should be pulled apart and carefully inspect the terminals (the metal parts) inside the connectors. See if they look corroded, burnt or possibly green in color versus the normal metal color you are probably used to seeing. You can get some electrical contact cleaner at any parts store if cleaning of the terminals is needed. If this is not possible, find some 91% rubbing alcohol and a light plastic bristle brush to clean them with. After that you should let the air dry, get some dielectric silicone compound (same stuff they use for light bulb sockets and spark plug wires) and put some where the terminals come into contact. Next, make sure that the tube that connects the turbocharger to the intake manifold is not leaking. Visually inspect all tube connections around the turbocharger and intake manifold. Tighten all hose as well as band clamps.

If you have a scan tool, clear the diagnostic trouble codes from memory, and see if this code returns. If it does not, then there is surely some issue in the connections. If the code does return, we will need to test the sensor and as well as the circuits with are related to it. There are 3 wires at the exhaust pressure sensor. Disconnect the harness going to the exhaust pressure sensor. You should use a digital volt ohm meter to test the 5V power supply circuit going to the sensor to insure it is being powered up. If there is 12 volts to the sensor when there should be 5 volts, repair the wiring from the PCM to the sensor for a short to 12 volts, or possibly a bad powertrain control module.

If you think its fine, then use a DVOM check to make sure you have 5V on the exhaust pressure sensor signal circuit. If there is no 5 volts to the sensor, or if you see 12 volts to the sensor, repair the wiring from the PCM to the sensor, or once again a possible bad PCM.

Then check to make sure you have a good ground at the exhaust pressure sensor. Connect a test light to 12V battery positive (red terminal) and touch the other end of the test light to the ground circuit going to the exhaust pressure sensor circuit ground. If the test light does not light up, this would indicate the problem circuit. If it does light up, wiggle the wiring harness going to each sensor to see if the test light flickers, indicating an intermittent connection. If all tests have passed so far, and you continue to get a P047B code, this would most likely indicate a failed exhaust pressure sensor, although a failed PCM could not be ruled out until you replace the sensor

Common Mistakes When Diagnosing The P047B Code

• The exhaust pressure sensor might be faulty
• Faults in the powertrain control module
• Some wiring problems