While there is a small chance that there is an issue with the running temperature of your engine, by far the most common issue with trouble code P0128 is a faulty thermostat. The exact location of the thermostat and issues related to a damaged thermostat may vary depending on your vehicle.
P0128 is an extension of OBD-II code P0 which indicates a problem with your car's coolant thermostat.
Although it may be possible to drive short distances with code P0128 set, you should get the issue fixed by a professional right away. Doing so will help ensure your vehicle keeps running at its best while also helping to prevent any additional damage.
Check the coolant level: If the level is lower than the minimum, add more coolant and go for a short drive. If the code is still active, you must change the thermostat. Inspect the coolant temperature sensor: The primary coolant temperature sensor is in the cylinder head near the thermostat.
This is referred to as a permanent code. This permanent code will go away on its own after the monitor runs and passes. Until then it will be present but only when read with a scan tool and will not turn the light on. If the problem Is detected again by the computer it will first set a pending code.
No, the coolant temperature sensor cannot be reset.
The engine coolant temperature sensor, or ECT is just a resistor affected by temperature—nothing's being stored on it and it has no software. The ECT works by receiving a signal from a computer called the engine control unit, or ECU.
A code P0128 may mean that one or more of the following has happened: Low engine coolant level Leaking or stuck open thermostat (likely) Faulty cooling fan (running too much) Faulty coolant temperature (ECT) sensor Faulty intake air temperature (IAT) sensor Possible Solutions Note: Please be sure the engine is turned ...
Replacing a Thermostat. You'll pay between $15 and $300 for the unit in addition to labor ($65 to $100 per hour) to replace an old thermostat with a new one. However, installing a brand-new thermostat is more involved and, therefore, more expensive.
If the old thermostat is positioned at the bottom of the radiator, you have no choice because all the coolant will drain by itself. If you drive with a bad thermostat, your car could overheat, causing severe and expensive engine damage.
If the coolant temperature sensor malfunctions, it could cause your car engine to get overheated. While sometimes a faulty sensor sends a permanent cold signal to the engine, it can also send a permanent hot signal.
Where is the Coolant Temperature Sensor located? The coolant temperature sensor will be located directly behind the coolant pipe. In most modern cars and vehicles, this is present behind the right cylinder head that is located right underneath the air intake pipe.
A car thermostat is designed to last a long time – typically around 100,000 miles or 10 years. However, various factors can impact its lifespan. First, driving conditions play a role. If you regularly drive in hot weather or stop-and-go traffic, your thermostat may suffer additional stress.
When your thermostat doesn;t respond to temperature conditions in your cooling system or gets stuck in either the open or closed position, it may cause a Check Engine Light to turn on. Ensure your thermostat is in good condition in order to prevent engine damage from excess heat.
This is an easy problem to solve yourself by simply removing the plastic outer casing and, with a very soft brush, delicately brushing off its coil and contact surfaces. It is most effective to clean the thermostat first at its lowest setting, then again at its highest setting.
Installation typically takes about 1 hour.
In most cases, installing a new thermostat is a relatively simple do-it-yourself project that can result in improved comfort and convenience and one that can help you save energy.
If your vehicle starts to use a lot more gasoline than usual, or black smoke is starting to come from the exhaust pipe, these are indicators that the coolant temperature sensor in your vehicle could be defective, and needs to be replaced.
While there is a small chance that there is an issue with the running temperature of your engine, by far the most common issue with trouble code P0128 is a faulty thermostat. The exact location of the thermostat and issues related to a damaged thermostat may vary depending on your vehicle.
Driving with a bad thermostat is like playing Russian roulette with your engine. The longer you drive with a faulty thermostat, the more you risk causing significant damage to your car. The engine might overheat, causing the head gasket to fail or even leading to a cracked engine block.
Most modern thermostats will have a clearly marked reset button inside the panel. It's usually small and recessed, so you might need a pointed object like a paperclip to press it. For those wondering specifically how to reset air conditioner thermostat models, the process is generally the same.
Loosen the top hose clip, then ease off the hose. Partially drain the cooling system first. With a normal top-mounted thermostat you need drain only part of the cooling system .