Description
OBD-II Trouble Code Description for P0118 Pontiac
Engine Coolant Temperature Circuit High
What does this mean?
OBD2 Code P0118 Pontiac 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 Pontiac
Symptoms of a P0118 Pontiac 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 Pontiac
A code P0118 Pontiac 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 Pontiac 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 Pontiac:
2010 Pontiac G8,2009 Pontiac G8,2009 Pontiac G6 ,2009 Pontiac G3,2008 Pontiac G8,2007 Pontiac Solstice SD-290 Concept,2007 Pontiac Solstice GXP,2007 Pontiac G6 GXP Show Car,2006 Pontiac Torrent,2006 Pontiac Solstice,2006 Pontiac Montana SV6,2006 Pontiac GTO,2006 Pontiac G6 GTP Coupe,2006 Pontiac G6 GTP Convertible,2005 Pontiac Vibe GT,2005 Pontiac Montana SV6,2005 Pontiac Grand Prix,2005 Pontiac Grand Am GT Coupe,2005 Pontiac GTO,2005 Pontiac G6 GT,2004 Pontiac Grand Prix GTP,2004 Pontiac Grand Am GXP,2004 Pontiac GTO 5.7,2004 Pontiac GTO,2004 Pontiac Bonneville GXP,2004 Pontiac Aztek Rally,2003 Pontiac Vibe GT,2003 Pontiac Vibe,2003 Pontiac Sunfire Coupe,2003 Pontiac Montana Thunder,2003 Pontiac Grand Prix,2003 Pontiac Grand Am SE Sedan,2003 Pontiac G6 Concept,2003 Pontiac Aztek,2002 Pontiac Sunfire GXP,2002 Pontiac Sunfire American Tuner,2002 Pontiac Solstice Concept,2002 Pontiac REV Concept,2002 Pontiac Grand Prix GXP,2002 Pontiac Grand Prix G-Force Concept,2002 Pontiac Firebird Trans Am Edition,2001 Pontiac Vibe GT,2001 Pontiac Vibe,2001 Pontiac Sunfire HO,2001 Pontiac Sunfire Accessorized,2001 Pontiac Montana,2001 Pontiac Grand Prix
Note:
1. The list of automotive Makes at the right edge of the screen. The currently selected ODB-ii codes is for the Pontiac 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.