Mercedes-Benz P0156 HO2S22 Sensor Range/Performance Condition

Description

OBD-II Trouble Code Description for P0156 Mercedes

O2 Sensor Circuit

What does this mean?

OBD2 Code P0156 Mercedes definition:
The o2 (oxygen) sensors measure oxygen content in the exhaust. The PCM (powertrain control module) then uses this information to regulate fuel injector pulse. The o2 sensors are very important for the proper operation of the engine. Innacurate or faulty o2 sensors can cause the PCM to add or take away fuel based on the faulty o2 sensor voltage which can cause a host of problems. A P0156 Mercedes code definition:the Bank 2,2 o2 sensor or the downstream (post-cat) o2 sensor on Bank 2. It is a four wire sensor. The PCM supplies a ground circuit and a reference voltage circuit of about 0.5 volts. Also for the o2 sensor heater element there is a battery voltage supply wire and another ground circuit for that. The o2 sensor heater allows the o2 sensor to warm up faster, thus achieving closed loop in less time than it would normally take for the exhaust to warm the sensor up to operating temperature. The O2 sensor varies the supplied reference voltage based on oxygen content in the exhaust. It is capable of varying from about 0.1 to 0.9 volts, 0.1 V indicating lean exhaust and 0.9 V indicating rich exhaust. This P0156 Mercedes code indicates that the Bank 2, 2 o2 sensor is stuck low for too long or isn’t active at all.

Symptoms

Possible sumptoms of OBD code P0156 Mercedes
Often post-cat o2 sensor problems present few symptoms since they are inputs to the PCM to monitor catalytic converter quality and don’t directly control fuel. sometimes no symptoms are noticeable. However the following may be possible on some vehicles: MIL (Malfunction Indicator Lamp) illumination Decrease in MPG Increase in tailpipe emissions

Causes

Possible causes of OBD code P0156 Mercedes
Potential causes of an P0156 Mercedes code include: Bad O2 sensor Signal shorted to voltage Wiring problems due to contact with exhaust components Holes in exhaust near o2 sensor

Possible Solutions

If you have access to a scan tool, check the signal voltage for the Bank 2,2 oxygen sensor with the engine at normal operating temperature. Is it stuck low currently? If so, increase RPM for a few seconds and see if it affects the reading. If it begins working with increased RPM, check for holes in the exhaust near the o2 sensor that may cause a false lean. If the exhaust pipe is intact, the sensor is sluggish, replace it. If the Bank 2,2 o2 sensor voltage reading remains low with increased RPM, unplug it and then observe the reading. It should have increased to about 0.5 volts or thereabouts. If it did, check for water intrusion or other connector problems. If none are found, replace the shorted o2 sensor. If the voltage reading is still stuck low after unplugging the sensor, then suspect a wiring problem. Using a voltmeter, with the o2 sensor unplugged, check for voltage on the signal circuit at the o2 sensor connector(PCM side). It can vary with model, but should be about 0.5 volts and not above 1 volt. If the voltage reading is too high, repair short to voltage on signal circuit. If the signal voltage checks out, suspect the PCM.

The OBD2 Code Information Be Applicable For Mercedes-Benz:

2013 Mercedes-Benz SLS AMG GT,2013 Mercedes-Benz SL65 AMG,2013 Mercedes-Benz SL550,2013 Mercedes-Benz SL500,2013 Mercedes-Benz SL-Class,2013 Mercedes-Benz GLK350 4Matic,2013 Mercedes-Benz GLK-Class,2013 Mercedes-Benz GL63 AMG,2013 Mercedes-Benz GL-Class,2013 Mercedes-Benz G63 AMG 6×6 Concept,2013 Mercedes-Benz G63 AMG,2013 Mercedes-Benz G550,2013 Mercedes-Benz G350 Bluetec,2013 Mercedes-Benz G-Class,2013 Mercedes-Benz E300 BlueTEC Hybrid,2013 Mercedes-Benz Citan,2013 Mercedes-Benz CLS Shooting Brake,2013 Mercedes-Benz A-Class AMG Sport,2013 Mercedes-Benz A-Class,2012 Mercedes-Benz SLS AMG Roadster,2012 Mercedes-Benz SLK55 AMG,2012 Mercedes-Benz SLK350,2012 Mercedes-Benz SLK250 CDI,2012 Mercedes-Benz SLK-Class,2012 Mercedes-Benz ML63 AMG,2012 Mercedes-Benz M-Class,2012 Mercedes-Benz E63 AMG Wagon,2012 Mercedes-Benz E63 AMG,2012 Mercedes-Benz CLS63 AMG,2012 Mercedes-Benz CLS550,2012 Mercedes-Benz CLS350 CDI,2012 Mercedes-Benz CLS-Class,2012 Mercedes-Benz C63 AMG,2012 Mercedes-Benz C-Class,2012 Mercedes-Benz B-Class,2011 Mercedes-Benz Vito,2011 Mercedes-Benz Viano,2011 Mercedes-Benz SLS AMG,2011 Mercedes-Benz S63 AMG,2011 Mercedes-Benz S600 Pullman Guard,2011 Mercedes-Benz R-Class,2011 Mercedes-Benz ML 63 AMG,2011 Mercedes-Benz G-Class,2011 Mercedes-Benz F125 Concept,2011 Mercedes-Benz E550 Cabriolet,2011 Mercedes-Benz E350 Cabriolet,2011 Mercedes-Benz E350 4Matic Wagon,2011 Mercedes-Benz E-Class L,2011 Mercedes-Benz E-Class Cabriolet,2011 Mercedes-Benz CL65 AMG,2011 Mercedes-Benz CL63 AMG,2011 Mercedes-Benz CL500,2011 Mercedes-Benz CL-Class,2011 Mercedes-Benz C-Class DR 520,2011 Mercedes-Benz B55 Concept,2011 Mercedes-Benz A-Class E-CELL,2011 Mercedes-Benz A-Class Concept,2010 Mercedes-Benz S65 AMG,2010 Mercedes-Benz S63 AMG,2010 Mercedes-Benz S400 BlueHYBRID,2010 Mercedes-Benz S-Class,2010 Mercedes-Benz ML450 Hybrid,2010 Mercedes-Benz GLK-Class,2010 Mercedes-Benz GL550,2010 Mercedes-Benz E63 AMG Estate,2010 Mercedes-Benz E63 AMG,2010 Mercedes-Benz E550 Coupe,2010 Mercedes-Benz E550,2010 Mercedes-Benz E350 Coupe,2010 Mercedes-Benz E350,2010 Mercedes-Benz E-Class,2010 Mercedes-Benz Biome Concept,2010 Mercedes-Benz B-Class F-Cell,2009 Mercedes-Benz SL65 AMG,2009 Mercedes-Benz SL63 AMG,2009 Mercedes-Benz SL-Class,2009 Mercedes-Benz ML 63 AMG,2009 Mercedes-Benz M-Class,2009 Mercedes-Benz G55 AMG,2009 Mercedes-Benz G-Class,2009 Mercedes-Benz CLS 63 AMG,2009 Mercedes-Benz CLS 280,2009 Mercedes-Benz CLC,2009 Mercedes-Benz B-Class,2009 Mercedes-Benz A-Class,2008 Mercedes-Benz SL,2008 Mercedes-Benz SLR,2008 Mercedes-Benz R-Class,2008 Mercedes-Benz CL65 AMG,2008 Mercedes-Benz C63 AMG,2008 Mercedes-Benz C-Class,2007 Mercedes-Benz S 63 AMG,2007 Mercedes-Benz S 600 Guard,2007 Mercedes-Benz S 500 4MATIC,2007 Mercedes-Benz S65 AMG,2007 Mercedes-Benz S550,2007 Mercedes-Benz R 63 AMG,2007 Mercedes-Benz G-Class,2007 Mercedes-Benz CL 63 AMG,2007 Mercedes-Benz CL 600,2007 Mercedes-Benz CL 500,2007 Mercedes-Benz CLS 63 AMG,2007 Mercedes-Benz CLS 350 CGI,2006 Mercedes-Benz SL 65 AMG,2006 Mercedes-Benz SL 600,2006 Mercedes-Benz SL 55 AMG,2006 Mercedes-Benz SL 500,2006 Mercedes-Benz SL 350,2006 Mercedes-Benz SLK 55 AMG SS,2006 Mercedes-Benz SL-Class,2006 Mercedes-Benz S-Class,2006 Mercedes-Benz R500,2006 Mercedes-Benz ML 63 AMG,2006 Mercedes-Benz ML500,2006 Mercedes-Benz ML350,2006 Mercedes-Benz GL 420 CDI,2006 Mercedes-Benz GL450,2006 Mercedes-Benz GL-Class,2006 Mercedes-Benz E 63 AMG,2006 Mercedes-Benz E-Class,2006 Mercedes-Benz CLK 63 AMG,2006 Mercedes-Benz B200 CDI,2006 Mercedes-Benz B150,2005 Mercedes-Benz SLK350,2005 Mercedes-Benz CLS500,2005 Mercedes-Benz CLK350,2005 Mercedes-Benz AClass

 

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