Description
OBD-II Trouble Code Description for P0478 Chrysler
Exhaust Pressure Control Valve High
What does this mean?
OBD2 Code P0478 Chrysler definition:
Exhaust Back Pressure Regulator – Is a variable position valve that controls exhaust back pressure during cold ambient temperatures to increase cab heat and decrease the amount of time needed to defrost the windshield. The PCM uses the measured exhaust back pressure, (ambient) intake air temperature, engine oil temperature and engine load to determine the desired exhaust back pressure. Valve position is controlled by switching the output signal circuit to 12 volts inside the PCM. On/off time is modulated from 0 to 99 % dependent upon the exhaust back pressure desired. Upon each initial engine start-up, the PCM exercises the exhaust back pressure valve by commanding it to cycle on and off once. If upon start-up the temperature of intake air sensed by the IAT sensor is < 37¡ãF (5¡ãC) and the oil temperature sensed by the EOT sensor is between 32¡ã-140¡ãF (0-60¡ãC) it will continue to keep the back pressure valve partially closed. As the oil temperature rises during engine operation, the PCM will control the valve in response to the rising oil temperature.
Symptoms
Possible sumptoms of OBD code P0478 Chrysler
– Engine Light ON (or Service Engine Soon Warning Light)
Causes
Possible causes of OBD code P0478 Chrysler
– Exhaust Back Pressure Valve The Error code is generally activated on detection of the following conditions: An open or shorted to ground control circuit can be detected by an on demand output circuit check performed during the engine off test. Problems with either the Exhaust Back Pressure Device or the tube between the exhaust manifold and the EBP sensor can be detected during the exhaust back pressure step test, in which the PCM commands and then measures a specific preprogrammed pressure and then measures time for pressure decay during the engine running test. If the PCM detects an EBP, EOT or IAT sensor fault it will disable the exhaust back pressure regulator.
Possible Solutions
Check the Exhaust Back Pressure Valve (EBPV) butterfly valve is opening and closing freely and not sticking. If it seems to move freely you can then check the connector and circuit for the EBPV solenoid.
The OBD2 Code Information Be Applicable For Chrysler:
2013 Chrysler Town and Country S,2013 Chrysler 300 Motown Edition,2013 Chrysler 300 Glacier,2012 Chrysler Ypsilon,2012 Chrysler Delta,2012 Chrysler 300 SRT8,2012 Chrysler 300 Luxury Series,2012 Chrysler 300C,2011 Chrysler Town and Country,2011 Chrysler 300,2011 Chrysler 200 S,2011 Chrysler 200 Convertible,2011 Chrysler 200,2009 Chrysler GEM Peapod,2009 Chrysler 200C EV Concept,2008 Chrysler ecoVoyager Concept,2008 Chrysler Town and Country,2008 Chrysler Sebring Convertible,2008 Chrysler EV Concept,2008 Chrysler 300C UK Version,2008 Chrysler 300C Touring UK Version,2008 Chrysler 300C Touring SRT UK Version,2008 Chrysler 300C SRT UK Version,2007 Chrysler Sebring UK Version,2007 Chrysler Sebring,2007 Chrysler Pacifica,2007 Chrysler PT Street Cruiser Pacific Coast Highway,2007 Chrysler Nassau Concept,2007 Chrysler Crossfire UK Version,2007 Chrysler Crossfire Roadster UK Version,2007 Chrysler Aspen,2006 Chrysler Imperial Concept,2006 Chrysler 300C SRT8 Touring,2006 Chrysler 300C Heritage Edition,2005 Chrysler Town and Country,2005 Chrysler PT Cruiser Convertible,2005 Chrysler Firepower Concept,2005 Chrysler Crossfire SRT6 Roadster,2005 Chrysler Crossfire SRT6,2005 Chrysler Crossfire Roadster,2005 Chrysler Akino Concept,2005 Chrysler 300C Touring,2005 Chrysler 300C SRT8,2005 Chrysler 300C,2005 Chrysler 300,2004 Chrysler Pacifica,2004 Chrysler ME FourTwelve Concept,2004 Chrysler Crossfire,2003 Chrysler Airflite Concept,2003 Chrysler 300M,2003 Chrysler 300C Touring Concept,2003 Chrysler 300C Concept,2002 Chrysler Pacifica Concept,2002 Chrysler California Cruiser Concept
Note:
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