Description
OBD-II Trouble Code Description for P0112 Honda
Intake Air Temperature Sensor 1 Circuit Low
What does this mean?
OBD2 Code P0112 Honda 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 Honda.
Symptoms
Possible sumptoms of OBD code P0112 Honda
There may be no noticeable symptoms of a P0112 Honda 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 Honda
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 Honda:
2013 Honda Urban SUV Concept,2013 Honda S660 Concept new,2013 Honda NSX-GT Concept,2013 Honda N-One,2013 Honda GEAR Concept,2013 Honda Civic,2013 Honda CR-Z,2012 Honda Civic,2011 Honda Jazz,2011 Honda Accord,2010 Honda Insight,2010 Honda CR-V,2009 Honda City,2008 Honda S2000,2008 Honda Accord,2007 Honda Fit,2007 Honda Civic,2007 Honda CR-V,2007 Honda Accord,2006 Honda Civic,2005 Honda Element,2005 Honda CRV SE,2005 Honda CRV EX,2003 Honda Element,2003 Honda CR-V,2002 Honda NSX,2002 Honda Civic Si,2002 Honda Accord SE,2001 Honda NSXR Concept,2001 Honda Model X Concept,2001 Honda Civic Si Concept,2001 Honda Civic Concept,2001 Honda CR-V,2001 Honda Accord Sedan,2001 Honda Accord Coupe,2000 Honda S2000,2000 Honda Passport,2000 Honda Insight
Note:
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