Description
OBD-II Trouble Code Description for P0405 Citroen
Exhaust Gas Recirculation Sensor “A” Circuit Low
What does this mean?
OBD2 Code P0405 Citroen definition:
There are different designs of EGR (Exhaust Gas Recirculation) systems, but they all operate in a similar way. The EGR valve is a PCM (Powertrain Control Module) controlled valve that allows measured amounts of exhaust gasses to pass back into the cylinders to be burned with the air/fuel mixture. Since exhaust gas is an inert gas that displaces oxygen, injecting it back into the cylinder can lower combustion temperatures which helps to improve NOx (oxides of nitrogen) emissions. EGR isn’t needed on cold startup or at idle. EGR is commanded on under certain conditions like startup or at idle. EGR is commanded on under certain conditions like partial throttle or decel depending on engine temperature and load, etc. Exhaust gasses are supplied to the EGR valve from an exhaust pipe or the EGR valve may be mounted directly in the exhaust manifold. When needed, the valve is commanded “on” allowing the gasses to pass into the cylinders. Some systems divert exhaust gasses directly into the cylinders while others simply inject it into the intake manifold where it is then pulled into the cylinders. while others simply inject it into the intake manifold where it is then pulled into the cylinders.
Some EGR systems are quite simple while others are a little more complicated. Electrically controlled EGR valves are directly controlled by the PCM. A wiring harness plugs into the valve itself and is commanded by the PCM as it sees the need. These can be 4 or 5 wire. Usually 1 or 2 grounds 12 volt ignition feed, a 5 volt reference circuit, and a feedback circuit. Other systems are vacuum controlled. These are quite simple. The PCM controls a vacuum solenoid which when activated, allows vacuum to travel to the EGR valve and open it. There should also be an electrical connector on this type of EGR valve for the feedback circuit. The EGR system feedback circuit allows the PCM to see if the EGR valve pintle is actually moving as it should. If the feedback circuit detects that the voltage is unusually low, or it’s position is lower than it’s commanded to be, P0405 Citroen may set.
Symptoms
Possible sumptoms of OBD code P0405 Citroen
MIL (Malfunction Indicator Lamp) illumination
Causes
Possible causes of OBD code P0405 Citroen
Short to ground in EGR signal or Reference circuits
Short to voltage in EGR ground or signal circuits
Bad EGR valve
Bad PCM wiring issues due to chafing or loose terminals
Possible Solutions
If you have access to a scan tool you can command the EGR valve on. If it responds and the feedback indicates the valve is moving properly then the problem may be intermittent. Sometimes in cold weather, moisture can freeze in the valve causing it to stick. After the vehicle warms up the problem may disappear. Carbon or other debris can lodge in a valve causing it to stick also
If the EGR valve doesn’t respond to your commands with the scan tool, disconnect the EGR harness connector. Turn the key to on position, engine off (KOEO). Using a voltmeter, check for 5 volts on the reference wire to the EGR valve. If there is no 5 volts, is there any voltage at all? If there is 12 volts, then repair short to voltage in the 5 volt reference circuit. If there is no voltage connect a test light to battery voltage and probe the 5 volt reference wire. If the test light illuminates, the 5 volt reference circuit is shorted to ground. Repair as necessary. If the test light doesn’t illuminate check for an open in the 5 volt reference circuit. Repair as necessary
If there is no apparent problem and there is no 5 volt reference, PCM may be at fault, however other codes will likely be present. If 5 volts are present on the reference circuit, jumper the 5 volts to the EGR signal circuit. Now the EGR position on the scan tool should read 100 percent. If it doesn’t connect test light to battery voltage and probe the EGR signal circuit. If it illuminates, then the signal circuit is shorted to ground. Repair as necessary. If the light doesn’t illuminate, check for an open on the EGR signal circuit. Repair as necessary.
If, after jumpering the 5 volt reference circuit to the EGR signal circuit the scan tool EGR position reads 100 percent, then check for poor terminal tension at the EGR valve connector. If the wiring is okay, replace the EGR valve.
The OBD2 Code Information Be Applicable For Citroen :
2013 Citroen Technospace Concept,2013 Citroen DS Wild Rubis Concept,2013 Citroen DS3 Cabrio Racing Concept,2013 Citroen Cactus Concept,2013 Citroen C4 L,2013 Citroen C4 Aircross,2013 Citroen C3 Picasso,2013 Citroen C1,2013 Citroen C-Elysee,2012 Citroen Numero 9 Concept,2012 Citroen DS5,2012 Citroen DS4 Racing Concept,2012 Citroen DS4,2011 Citroen Tubik Concept,2011 Citroen DS3 Racing,2011 Citroen DS3 R3,2011 Citroen DS3,2011 Citroen C5,2011 Citroen C4,2011 Citroen C-Zero,2010 Citroen Survolt Concept,2010 Citroen Metropolis Concept,2010 Citroen Lacoste Concept,2010 Citroen GQ Concept,2010 Citroen DS High Rider Concept,2010 Citroen C3,2009 Citroen REVOLTe Concept,2009 Citroen DS Inside Concept,2009 Citroen C4 Coupe,2009 Citroen C4,2009 Citroen C3 Pluriel Charleston,2009 Citroen C3 Picasso,2009 Citroen C2,2009 Citroen C1,2009 Citroen Berlingo Multispace,2008 Citroen Hypnos Concept,2008 Citroen GT Concept,2008 Citroen C5 Estate,2008 Citroen C5,2008 Citroen C4 notchback,2008 Citroen C4 WRC HYmotion4 Concept,2008 Citroen C4 Sedan,2007 Citroen Grand C4 Picasso,2007 Citroen Cruise Crosser Concept,2007 Citroen C5 Airscape Concept,2007 Citroen C4 Picasso,2007 Citroen C-Crosser,2007 Citroen C-Cactus Concept,2006 Citroen C6,2006 Citroen C3 X-TR,2006 Citroen C3 VTR,2006 Citroen C3 Pluriel,2006 Citroen C3,2006 Citroen C1 5door,2006 Citroen C1 3door,2006 Citroen C-Metisse Concept,2006 Citroen C-Buggy Concept,2005 Citroen C5 Break,2005 Citroen C5,2005 Citroen C4 Coupe with Panoramic Sunroof,2005 Citroen C4 Coupe Enterprise,2005 Citroen C4 Coupe,2005 Citroen C4,2005 Citroen C-SportLounge Concept Car,2005 Citroen C-Airplay Concept,2004 Citroen Xsara Picasso,2004 Citroen C4 Sport Concept,2004 Citroen C3 Pluriel HDi 70,2004 Citroen C2,2003 Citroen CAirlounge Concept,2003 Citroen C8 Exclusive,2002 Citroen C-Airdream Concept,2001 Citroen Xsara Picasso,2001 Citroen C-Crosser Concept
Note:
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