Description
OBD-II Trouble Code Description for P0118 Cadillac
Engine Coolant Temperature Circuit High
What does this mean?
OBD2 Code P0118 Cadillac definition:
The engine coolant temperature (ECT) sensor is a thermistor screwed into a coolant passage in the cylinder head. Sensor resistance is high when coolant temperature is low and resistance drops when coolant temperature increases. The powertrain control module (PCM) provides a 5 volt reference and a ground to the sensor. The PCM monitors voltage drop to determine coolant temperature. If the ECT reads less than freezing temp. when engine has been running for more than a few minutes, the PCM determines a circuit fault and sets this code. Or if the PCM determines the sensor resistance is out of specs, this code is set.
Symptoms
Possible sumptoms of OBD code P0118 Cadillac
Symptoms of a P0118 Cadillac could include: Very poor fuel economy A no start condition Vehicle may start, but run very poorly, blowing black smoke, running very rough and misfiring Illumination of MIL
Causes
Possible causes of OBD code P0118 Cadillac
A code P0118 Cadillac may mean that one or more of the following has happened: A bad connection at the sensor An open in the ground circuit between the ECT sensor and the PCM A short in the voltage feed between the sensor and the PCM A bad PCM (less likely) A bad temperature sensor (shorted internally)
Possible Solutions
First, if you have access to a scan tool, check the reading of the coolant sensor. Does it read a logical number? If so, the problem is likely intermittent. Perform a “wiggle” test by wiggling the connector and harness to the sensor while watching the reading on the scan tool. Watch for any drop-outs. Drop-outs would indicate a bad connection. If the scan tool reads an illogical temperature, check the resistance of the temperature sensor. If it is out of specs, replace it. If it is in specifications, unplug the sensor and, using a fused jumper wire, jumper the two terminals of the connector together. The temperature reading should now be maxed out to above 250 degrees F. If not, there is likely a problem with the ground circuit or voltage supply. Check for 5 volts reference voltage at the connector. Also check for ground presence at the connector. If you do not have 5V ref. and/or ground continuity, check for these back at the PCM connector. If you have these at the PCM connector, then repair open or short between the PCM and the sensor. If you do not, remove the offending wire from the PCM and then check for proper voltage at the PCM pin. If it’s present now, repair short on the circuit. If it isn’t present after removing the wire and checking the pin, replace PCM NOTE: Usually, P0118 Cadillac is indicative of a bad temperature sensor, but doesn’t rule out these other possibilities. If you’re unsure of how to diagnose a PCM, do not attempt.
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:
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