Engine-CodesNissan – P0128 Nissan

P0128 Nissan Code - Thermostat Function

Quick Answer

The P0128 code for Nissan vehicles indicates an issue with the thermostat function. Common causes include Faulty thermostat, Low coolant level, Coolant leaks. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P0128 Nissan indicates Thermostat Function.
Common causes
Common causes include Faulty thermostat, Low coolant level, Coolant leaks.
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Table of contents Created and updated by William Orellana on Sep 06, 2024
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Code P0128 Nissan Description

The P0128 code for Nissan vehicles indicates an issue with the thermostat function. The thermostat is a crucial component of the vehicle's cooling system, regulating the engine's operating temperature by controlling the flow of coolant. When this code is triggered, it typically means that the engine is not reaching the expected temperature within a specified time frame. This can lead to inefficient fuel combustion, reduced engine performance, and potential damage to engine components over time.

OBDII Code P0128 Nissan - Thermostat Function
P0128 Nissan Code - Thermostat Function

Common Causes of P0128 Nissan

  1. Faulty thermostat
  2. Low coolant level
  3. Coolant leaks
  4. Thermostat stuck in open position
  5. Faulty engine coolant temperature sensor

Symptoms of P0128 Nissan

  1. Engine running colder or hotter than normal
  2. Decreased fuel efficiency
  3. Poor heater performance
  4. Check Engine Light illuminated
  5. Engine overheating or running hot

How to Fix P0128 Nissan

  1. Check coolant level and top off if necessary
  2. Inspect for coolant leaks and repair as needed
  3. Test thermostat operation and replace if faulty
  4. Replace engine coolant temperature sensor if necessary
  5. Clear the diagnostic trouble codes and test drive the vehicle to ensure the issue is resolved

Cost to Fix P0128 Nissan

The typical repair costs for addressing a P0128 code in a Nissan vehicle can range from $150 to $400, including parts and labor. However, as mentioned earlier, actual costs can vary depending on the specific diagnosis time, rates at auto repair shops, and any additional repairs or parts needed. It is recommended to consult with a local auto repair shop for a more accurate estimate.

Tech Notes for P0128 Nissan

If the cooling system is not leaking and the fluid level is OK, replacing the thermostat usually takes care of the problem.

There is a factory service bulletin for all Nissan Models 2002 and Up, with the P0128 and remote starter system. Bulletin information:

IF CONFIRM
The MIL is “ON” with P0128 (Thermostat Function) stored.
ACTIONS
1. Check to see if an aftermarket remote starter system is installed. Remote starter systems may cause the MIL to illuminate and DTC P0128 to store.
2. If a remote starter system is installed, remove/disconnect it before performing diagnostic procedures on the vehicle.

When is the Code Detected?

The engine coolant temperature does not reach to specified temperature even though the engine has run long enough.

Need more information about the P0128 Nissan code?

Need more information on how to fix the P0128 Nissan code? Get Access to Factory Service Manuals

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Information for Specific Nissan Models

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0128 Nissan Code

1. What are the common symptoms of an OBDII code P0128 in a Nissan?

- Common symptoms include the engine running colder than normal, reduced fuel efficiency, and a possible increase in emissions.

2. What is the function of the thermostat in a Nissan related to the P0128 code?

- The thermostat regulates the engine temperature by controlling the flow of coolant, ensuring the engine operates at the optimal temperature range.

3. What are the typical causes of an OBDII code P0128 in a Nissan?

- Common causes include a faulty thermostat, a malfunctioning engine coolant temperature sensor, low coolant levels, or a stuck open thermostat.

4. How can I diagnose the cause of an OBDII code P0128 in my Nissan?

- Diagnosing the issue involves checking the coolant level, inspecting the thermostat for proper operation, and testing the engine coolant temperature sensor for accuracy.

5. Can a defective thermostat cause an OBDII code P0128 in a Nissan?

- Yes, a defective thermostat that is stuck open can trigger the OBDII code P0128 by preventing the engine from reaching the correct operating temperature.

6. How should I proceed with repairing an OBDII code P0128 in my Nissan?

- The most common repair for this code is replacing the thermostat with a new one, ensuring it functions correctly and allows the engine to reach the optimal temperature.

7. Are there any DIY tips for fixing an OBDII code P0128 in a Nissan?

- While replacing the thermostat may be straightforward for some DIY enthusiasts, it's recommended to consult a professional mechanic to ensure proper diagnosis and repair.

8. Can driving with an OBDII code P0128 in a Nissan cause further damage?

- Continuously driving with this code may lead to reduced engine efficiency, potential overheating issues, and increased wear on engine components, so prompt repair is advised.

9. Is it safe to continue driving my Nissan with an OBDII code P0128?

- It's generally not recommended to drive with this code as it can affect the engine's performance and efficiency, potentially leading to more serious issues over time.

10. How often should the thermostat be replaced in a Nissan to prevent OBDII code P0128?

- Thermostats typically have a lifespan of around 5-7 years or 50,000-70,000 miles, so consider replacing it preventively within this interval to avoid triggering the P0128 code.

Discuss the causes and fixes for P0128 Nissan OBDII Code

  • I will chenge the coolant termostat, but I think this morning my nissan sentra didn't warm up so it come this

  • why does the heater works if the thermostat is not good?

  • Probably the thermostat is stuck open.

  • The thermostat is to control the coolant flow to the radiator, it doesn't have anything to do with the flow to the heater.

  • So I have this code but my temp gauge is working fine, car is not overheating or taking an abnormal amount of time to warm up. Coolant level is right on. What else could be the issue.

  • The code doesn't really mean that the thermostat is damage, the at some point it may go stuck causing the coolant temperature to go out of factory specifications. You should try erasing the code first and if comes back you could start by changing the coolant and if possible the thermostat as well. What model and year is your Nissan and when was the last time you service the coolant system?

  • on a versa 2002 up to now the installation of secondary market remote-start often cause a p0128. unplug it , clear code and run-test . tsb (NTB10-079)

  • Than you for the information!!! Bulletin information added.

  • so what do I do now?

  • See "Possible Causes" above. If the possible cause is the thermostat, then you have to replace the thermostat and clear the code.

  • help me Nissan altima 2003 p0128 and p0328 but have remove the thermostat sensor in side the Engine bcos I'm using the car in Nigeria and i replaced knock sensor is still bring the too code what can I do to fix it

  • Is the engine overheating? any coolant leaks? Try installing a new thermostat. You may be getting the P0128 because there is no thermostat.

  • what of the knock sensor

  • If the engine is overheating the engine will knock and that may set the knock sensor code.

  • No the Engine is not Overheating bcos have already remove the thermostat what cost the knock sensor code and I replaced it is still bring the knock sensor code

  • the Engine is not do Overheating and I replaced the knock sensor is still bring the code pls what can I do to fix it

  • My only suggestion my friend is to install back the thermostat, and if the code comes back, then you need to check the wires from the sensor to the ECM.