Description
OBD-II Trouble Code Description for P0118 Hummer
Engine Coolant Temperature Circuit High
What does this mean?
OBD2 Code P0118 Hummer 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 Hummer
Symptoms of a P0118 Hummer 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 Hummer
A code P0118 Hummer 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 Hummer 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 Hummer:
2009 Hummer H3T Alpha,2008 Hummer HX Concept,2008 Hummer H3 Wagon Concept,2008 Hummer H3 Alpha,2008 Hummer H2,2007 Hummer H3 Open Top,2007 Hummer H3X,2007 Hummer H3R Off Road Concept,2007 Hummer H2 Safari Concept,2006 Hummer H3,2006 Hummer H2 SUT Limited Edition,2006 Hummer H1 Alpha,2005 Hummer H3 Street,2005 Hummer H2 SUT,2004 Hummer H2 SUT Concept,2004 Hummer H2H Hydrogen Concept,2004 Hummer H2,2004 Hummer H1,2003 Hummer Humvee Military Vehicle,2003 Hummer H3T Concept,2003 Hummer H2 with GM Accessories,2003 Hummer H2 SUV,2003 Hummer H2 SUT Dirt Sport Concept,2003 Hummer H1,2003 Hummer Bike,2002 Hummer H2 SUV Concept,2002 Hummer H1 10th Anniversary Edition,2002 Hummer H1,2001 Hummer H1 Alpha Concept
Note:
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