Description
OBD-II Trouble Code Description for P0112 Mercedes
Intake Air Temperature Sensor 1 Circuit Low
What does this mean?
OBD2 Code P0112 Mercedes definition:
The IAT (intake air temperature) sensor simply measures the temperature of air that is entering the engine. Intake air temperature is important because the higher the intake air, the higher the combustion temperatures. High combustion temperatures result in increased Nox (Nitrogen oxides) emissions. To keep these higher temps from causing increased combustion temps, the intake air tubing should be intact, allowing the engine to “breathe” air that isn’t sampled from the engine compartment. The IAT measures air temp by using a thermistor, or a thermometer of sorts. The thermistor is supplied 5 volts reference voltage from the PCM (powertrain control module) and a ground. Usually, when the air temperature is cold the resistance in the thermistor is high and when the air temperature is warmer, the resistance decreases. This change in resistance changes the 5 V reference from the PCM, thereby informing the PCM of the temperature of incoming air. If the PCM notices that the incoming air temp is unusually high, say, 300 degrees, when the engine temp is still relatively low, it will set a P0112 Mercedes.
Symptoms
Possible sumptoms of OBD code P0112 Mercedes
There may be no noticeable symptoms of a P0112 Mercedes code other than an MIL (Malfunction Indicator Lamp). However, a emissions test may reveal higher Nox readings depending on the type of IAT failure. Or the engine may ping under load, depending on the type of IAT failure.
Causes
Possible causes of OBD code P0112 Mercedes
No reference voltage to the IAT sensor due to an open wire Excessively high intake air temperatures Short to ground on signal circuit Damaged IAT connector Bad PCM
Possible Solutions
Hook up your scan tool or code reader and read the IAT reading. With a cold engine, the IAT should roughly match the coolant reading, since both will read ambient temperature. If the IAT is reading excessively high, check the IAT connector for damage. If you find none, unplug the IAT sensor and recheck the reading. It should now read the minimum, around -20 deg. If it does, then replace the IAT sensor. But, if the reading is still high, unplug the sensor and check for resistance across the two wiring harness terminals. If there is infinite resistance, then the PCM itself is bad. If the resistance isn’t infinite, then check and repair the short to ground on the signal circuit.
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
Note:
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