What is the P0407 fault code What is the description of the Exhaust Gas Recirculation (EGR) Sensor “B” Circuit Low malfunction? How do I fix the P0407 fault code What are the symptoms and causes for the P0407 fault code
What is the P0407 Fault code? What does it all mean?
If the powertrain controller module (PCM), detects a voltage signal coming from the exhaust gas regeneration (EGR) sensor circuit, “B”, that is too low in comparison to the manufacturer’s specifications, a P0407 code will be activated.
EGR systems can have different designs but all work in the same way. The PCM controls the EGR valve. It sends certain amounts to the cylinders so that it can be mixed with the fuel mixture. By lowering the combustion temperature, the exhaust gases are returned to the cylinders. This helps reduce NOx (oxides nitrogen) emission.
When the engine is at low revs, cold, or idling, the EGR valve closes. The PCM allows for the EGR valve’s opening under certain conditions. These conditions are determined by engine temperature and RPM. The EGR valve can be found on the exhaust manifold. Exhaust gas is fed to it through an exhaust tube. Some systems send exhaust gases directly into the cylinders. Others send them to an intake manifold, where they are drawn into the cylinders.
Some EGR systems have simple designs, while others are more complex. The PCM controls the electric EGR valves via a harness. These valves can have 4 or 5 wires. The ground circuits are typically 1 or 2 ground, 12 volt power supply and 5 volt reference, as well as 1 feedback circuit. Vacuum-controlled EGR valves are a bit simpler. The PCM controls an EGR valve’s vacuum solenoid. This EGR valve uses an electrical connector to provide feedback. The feedback circuit is used by the PCM to control the position and operation of the EGR valve.
Mistake code P0407 is issued to the PCM if it receives an abnormally low voltage from the feedback circuit. The code is very similar to P0405. The only difference is that P0405 refers the “A” sensor and P0407 the “B” sensors. The location of the sensors “A” or “B” can be found in the vehicle’s specific repair manual.
P0407 fault codes can be found on vehicles made by Ford, Audi and Seat.
What causes the P0407 Fault code?
Here are some reasons why P0407 should be set.
- – Defective EGR valve
- – Broken wires or loose connectors that are open to the EGR valve circuit.
- – Carbon formation in EGR valve
- – Defective EGR solenoid
- – Vacuum to EGR solenoid
- – Defective EGR valve position sensor
What are the symptoms for P0407 fault code?
These symptoms may be present in vehicles with code P0407.
- – Illumination at the check engine lights
- – Engine hesitation during acceleration
- – Increased exhaust emission
- – Increased fuel consumption
How to Fix the P0407 Fault Code
The following repairs may be able to resolve the P0407 fault codes:
- – Replacing the EGR valve that is faulty
- – Removal of carbon residues from the EGR valve
- Repair damaged, broken wires or loose, corroded connects that are causing an open, short circuit.
- Repair of vacuum hoses that have been damaged, punctured, or cracked in vacuum-operated EGR systems
- – Replacing the EGR solenoid.
- – Replacing the defective EGR position sensor
You can clean carbon deposits from the EGR valve by using special cleaning sprays. This will usually resolve the problem.
How serious is the P0407 Fault code?
This code will not allow you to drive on the roads. However, if the code P0407 is activated, the PCM will disable your EGR system. The vehicle’s emissions will rise and an engine fault light will be displayed. You can avoid potential failures by addressing the problem as soon as possible.
