What is P0474 fault code? Exhaust Pressure Sensor Intermittent fault code: What causes it? How do you fix the fault code P0474 What are the symptoms and causes for the P0474 error code?
What is the P0474 Fault code? What does it all mean?
If the powertrain controller module (PCM), detects that voltage signal from exhaust pressure sensor is irregular, intermittent, or unreasonable, P0474 will trigger. This is often due to an electrical fault. This code can also be used to set the P0471,P0472, and P0473 fault codes.
Induction is when compressed air is delivered to an internal combustion motor’s inlet. These engines are equipped with a compressor which compresses air to increase pressure, temperature, density and volume. As the engine receives more air, the engine also gets more fuel. Conclusion; When a small displacement engine needs extra power and the turbocharger/supercharger kicks in, it will have the same power output as a large displacement engine.
The powertrain control module, or PCM, uses a variety of actuators and sensors to fine-tune turbocharger systems. This improves power output and fuel economy. One of these sensors, the exhaust pressure sensor EPS (exhaust gas recirculation), plays a crucial role in emissions and turbo systems. All these systems are dependent on reliable and accurate input data from the exhaustpressure sensor.
The exhaust pressure sensor can be found in turbo diesel engines. Its primary function is to determine the amount of exhaust back pressure and send it to the PCM. The amount of particulate matter (soot), retained by the DPF (Diesel Particulate filter) is directly related to exhaust back pressure, especially in diesel applications.
Excessive soot buildup in the DPF causes the exhaust to clog, which prevents the flow of exhaust gasses. The PCM uses the exhaust backpressure to determine how clogged the DPF. The PCM uses input data from sensors to determine if the DPF has become clogged. If it does, the PCM injects a chemical fuel or chemical into exhaust system. This raises the exhaust gas temperature, and starts a process called “The Process of Clogging”. “regeneration” Burn the exhaust.
Some applications use the input data from an exhaust pressure sensor to control the operation of the EGR or the turbocharger boost. Continuous monitoring of the pressure in the exhaust system between the turbocharger and the cylinders is done. This sensor is used by the PCM to monitor turbocharger function and control the wastegate.
The PCM compares voltage signals from the exhaust backpressure sensor and the ambient air pressure. If it detects that the voltage signal from the sensor does not match with the other sensors, it receives an intermittent/intermittent signal from the sensor, or no voltage signal at all, it sets the P0474 fault code.
P0474 fault codes can be found on vehicles made by Volkswagen, Ford and Mercedes-Benz.
What causes the P0474 Fault code?
The following are the most frequent causes of the P0474 error code:
- – Defective exhaust Pressure Sensor
- – Sensors that are damaged, frayed, or fused wires, or loose, rusty connectors. This can cause the sensor to fail.
- – Short to ground, from exhaust pressure sensor to PCM
- – Blockage of the exhaust back pressure tube
- – A blockage in the pipe connecting the exhaust manifold and the pressure sensor
- – Leakage of air in the EVAP (exhaust gas recirculation) system
- – A PCM that is not working or requires a software upgrade
What are the symptoms of P0474 Malfunction code?
These symptoms may be present in vehicles with code P0474.
- – Illumination at the check engine lights
- – Low engine performance
- – The turbocharger system fails
- – Increased fuel consumption
- – It is possible to adjust fault codes related to turbocharger and exhaust systems
- – Unable to perform the regeneration process manually
- – The computer will not turn on unless it can be regenerated.
How do I fix the P0474 fault code?
The EGR valve is typically located next to the exhaust backpressure pipe. When diagnosing and fixing code P0474, the most common error is to confuse the fault with EGR valve. Both of these faults can be completely different.
There are several repairs that can resolve the P0474 fault code:
- – Check the exhaust pressure sensor and replace it if necessary
- Repair/replacement damaged wires or connectors to the sensor that are causing an open circuit or short circuit
- – Inspection of the ground cable from the PCM and repair of any damaged cables
- – Cleaning out the exhaust pipes that are blocked
- – Repair of parts that leak exhaust or air.
- – Reprogramming or replacement of a faulty PCM
- Locate the exhaust pressure sensor. Then disconnect the pipe connecting the sensor to the intake manifold. Inspect the exhaust pressure sensor for any carbon buildup. You might see water coming out of the code.
- Cables and connectors should be checked for any burnt areas or rubbing against other components. You should also inspect the connector terminals to ensure they are free from corrosion. Replace these components if there is a problem.
- Ensure that the pipe connecting to the turbocharger and the intake manifold are not leaking. If you find any bad links, make adjustments and delete the code.
- – If the code does not return, check the circuits and the sensor. Disconnect the wires connecting to the exhaust pressure sensor. Test the power circuit with a DVOM, Digital Volt-Ohm Meter. Repair the wiring connecting the PCM and sensor if the sensor is reading 12 volts.
- – If none of these options work, replace your exhaust pressure sensor.
What is the P0474 Fault Code?
The engine may not be performing as it should if you continue to drive the vehicle bearing the P0474 fault codes. Rarely, an engine may not start at all in some cases. You could end up stranded on a roadside due to your vehicle not starting.
