Description
OBD-II Trouble Code Description for P0112 Cadillac
Intake Air Temperature Sensor 1 Circuit Low
What does this mean?
OBD2 Code P0112 Cadillac 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 Cadillac.
Symptoms
Possible sumptoms of OBD code P0112 Cadillac
There may be no noticeable symptoms of a P0112 Cadillac 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 Cadillac
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 Cadillac
2013 Cadillac XTS,2013 Cadillac Elmiraj Concept,2013 Cadillac ATS,2012 Cadillac SRX,2011 Cadillac Ciel Concept,2011 Cadillac CTS Coupe,2011 Cadillac CTS-V Sport Wagon,2011 Cadillac CTS-V Coupe Race Car,2011 Cadillac CTS-V Coupe,2011 Cadillac CTS-V Black Diamond Edition,2010 Cadillac XTS Platinum Concept,2010 Cadillac Urban Luxury Concept,2010 Cadillac SRX,2010 Cadillac SLS,2010 Cadillac CTS Sport Wagon,2010 Cadillac Aera Concept,2009 Cadillac Presidential Limousine,2009 Cadillac Escalade Hybrid,2009 Cadillac Converj Concept,2009 Cadillac CTS-V,2008 Cadillac STS,2008 Cadillac Provoq Concept,2008 Cadillac Escalade Platinum,2008 Cadillac CTS Coupe Concept,2008 Cadillac CTS,2008 Cadillac BLS Wagon,2007 Cadillac SRX European Version,2007 Cadillac SLS,2007 Cadillac Escalade European Version,2007 Cadillac Escalade EXT,2007 Cadillac Escalade ESV,2007 Cadillac Escalade,2007 Cadillac BLS Sport,2006 Cadillac XLR Star Black Limited Edition,2006 Cadillac XLRV,2006 Cadillac STSV,2006 Cadillac SRX,2006 Cadillac Escalade ESVe Limousine,2006 Cadillac DTS Limousine,2006 Cadillac DTS,2006 Cadillac CTS,2006 Cadillac BLS,2005 Cadillac XLR Euro,2005 Cadillac STS SAE 100,2005 Cadillac STS Euro,2005 Cadillac STS,2005 Cadillac SRX Euro,2005 Cadillac SRX,2005 Cadillac CTS Euro,2005 Cadillac CTS-V Euro,2005 Cadillac BLS Show Car,2004 Cadillac XLR,2004 Cadillac Seville SLS,2004 Cadillac SRX,2004 Cadillac Escalade ESV Platinum,2004 Cadillac Escalade ESV Executive Edition,2004 Cadillac DeVille Armored,2004 Cadillac CTSV Race Car,2004 Cadillac CTSV,2004 Cadillac CTS,2003 Cadillac Sixteen Concept,2003 Cadillac Escalade EXT,2003 Cadillac Escalade ESV,2003 Cadillac CTSV with Accessories,2003 Cadillac CTS,2002 Cadillac Vizon Concept,2002 Cadillac Seville STS,2002 Cadillac Escalade EXT,2002 Cadillac Escalade,2002 Cadillac DeVille,2002 Cadillac Cien Concept,2001 Cadillac Seville,2001 Cadillac Eldorado,2001 Cadillac DeVille Presidential Limousine,2001 Cadillac DeVille DTS,2000 Cadillac Seville STS,2000 Cadillac Imaj Concept,2000 Cadillac Escalade,2000 Cadillac Eldorado ETC,2000 Cadillac DeVille
Note:
1. The list of automotive Makes at the right edge of the screen. The currently selected ODB-ii codes is for the Cadillac makes.
2. Look up the other OBD II Trouble Codes, please use the search box. Enter the 5 character trouble codes in the search box and submit the search.
3. Don’t assume a particular OBD-II code means the same for other auto manufacturers as there are many makes specific codes in use.
4. If your OBD-II trouble codes are for a different car, select that vehicle series before searching for the diagnostic codes because not all OBD2 codes used by one manufacture are used by the other makes.
5. The information contained on this site is presented for informational purposes only. We are not responsible for any actions you take on your vehicle. If you have any doubt as to repairs on your vehicle, please contact your technician.