Description
OBD-II Trouble Code Description for P0128 Jeep
Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
What does this mean?
OBD2 Code P0128 Jeep definition:
This means that the engine’s PCM detected that the engine has not reached the required temperature level within a specified amount of time after starting the engine. The intent of the P0128 Jeep code is to indicate a faulty thermostat. Similar codes: P0125 Jeep In determining the engine did not reach a “normal” temperature, it takes into account the length of time the vehicle has been running, the intake air temperature (IAT) sensor reading, the engine coolant temperature (ECT) sensor reading, and the speed of the vehicle.
Symptoms
Possible sumptoms of OBD code P0128 Jeep
You will likely not notice any drivability problems other than the MIL illumination.
Causes
Possible causes of OBD code P0128 Jeep
A code P0128 Jeep may mean that one or more of the following has happened: Low engine coolant level Leaking or stuck open thermostat Faulty cooling fan (running too much) Faulty coolant temperature (ECT) sensor Faulty intake air temperature (IAT) sensor
Possible Solutions
Past experience indicates that the most likely solution is to replace the thermostat. However here are some suggestions on troubleshooting and repairing a P0128 Jeep OBD-II code: Verify coolant strength & level Verify proper cooling fan operation (check if it’s running more than it should). Replace if necessary. Verify proper engine coolant temperature (ECT) sensor operation, replace if necessary. Verify proper intake air temperature (IAT) sensor operation, replace if necessary. If the above items check out good, replace the thermostat If Nissan vehicle, check for Technical Service Bulletins (TSBs), as the ECM may need to be reprogrammed to correct the P0128 Jeep code
The OBD2 Code Information Be Applicable For Jeep:
,2013 Jeep Wrangler Unlimited Moab,2013 Jeep Wrangler Rubicon 10th Anniversary,2013 Jeep Grand Cherokee Trailhawk,2012 Jeep Wrangler Unlimited Altitude,2012 Jeep Wrangler Freedom Edition,2012 Jeep Wrangler Dragon Concept,2012 Jeep Wrangler Call of Duty MW3,2012 Jeep Wrangler Arctic,2012 Jeep Wrangler,2012 Jeep Liberty Arctic,2012 Jeep Grand Cherokee SRT8,2012 Jeep Grand Cherokee Concept,2011 Jeep Wrangler Mojave,2011 Jeep Wrangler Call of Duty Black Ops,2011 Jeep Wrangler,2011 Jeep Patriot,2011 Jeep Grand Cherokee UK Version,2011 Jeep Grand Cherokee,2011 Jeep Compass,2009 Jeep Wrangler Unlimited EV,2009 Jeep Patriot EV,2008 Jeep Wrangler Unlimited UK Version,2008 Jeep Wrangler UK Version,2008 Jeep Renegade Concept,2008 Jeep Patriot Back Country Concept,2008 Jeep Liberty,2008 Jeep Grand Cherokee S-Limited UK Version,2008 Jeep Grand Cherokee Overland UK Version,2008 Jeep Grand Cherokee,2008 Jeep EV Concept,2008 Jeep Cherokee,2007 Jeep Wrangler Unlimited,2007 Jeep Wrangler Rubicon,2007 Jeep Trailhawk Concept,2007 Jeep Patriot UK Version,2007 Jeep Patriot,2007 Jeep Grand Cherokee UK Version,2007 Jeep Grand Cherokee SRT-8 UK Version,2007 Jeep Compass UK Version,2007 Jeep Compass,2007 Jeep Commander UK Version,2006 Jeep Grand Cherokee SRT8,2006 Jeep Commander 4×4 Limited 5.7 HEMI,2005 Jeep Wrangler UK Version,2005 Jeep Patriot Concept,2005 Jeep Liberty Renegade 3.7,2005 Jeep Liberty CRD Limited,2005 Jeep Hurricane Concept,2005 Jeep Grand Cherokee 5.7 Limited,2005 Jeep Gladiator Concept,2005 Jeep Compass Concept,2005 Jeep Cherokee UK Version,2004 Jeep Wrangler Unlimited,2004 Jeep Rescue Concept,2003 Jeep Treo Concept,2003 Jeep Grand Cherokee UK Version,2003 Jeep Cherokee UK Version,2003 Jeep Cherokee Renegade,2002 Jeep Willys2 Concept
Note:
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