P0128 Lexus Code - Coolant Thermostat
Quick Answer
The ECM estimates the engine coolant temperature based on the starting temperature, engine loads, and engine speeds. Common causes include Leaking or stuck open thermostat, Low engine coolant level, Insufficient warm up time. 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 Lexus indicates Coolant Thermostat.
- Common causes
- Common causes include Leaking or stuck open thermostat, Low engine coolant level, Insufficient warm up time.
- 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.
Code P0128 Lexus Description
What are the Possible Causes of the DTC P0128 Lexus?
- Leaking or stuck open thermostat
- Low engine coolant level
- Insufficient warm up time
- Faulty Engine Coolant Temperature (ECT) sensor
- Engine Coolant Temperature sensor harness is open or shorted
- Engine Coolant Temperature sensor electrical circuit poor connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0128 Lexus?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0128 Lexus code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P0128 Lexus code?
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Need Help with the Code?
Get the P0128 Lexus code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0128 Lexus Code
1. What are common symptoms of OBDII code P0128 in a Lexus related to the coolant thermostat?
Symptoms may include engine running colder than normal, slow engine warm-up, poor fuel economy, and potential overheating.
2. What are possible causes of the P0128 code in a Lexus?
Common causes include a faulty thermostat, low coolant level, a malfunctioning coolant temperature sensor, or issues with the cooling system.
3. How can I diagnose the P0128 code in a Lexus related to the coolant thermostat?
Diagnosis typically involves checking the coolant level, inspecting the thermostat for proper operation, testing the coolant temperature sensor, and examining the overall cooling system for any leaks or blockages.
4. Can I continue driving my Lexus with the P0128 code present?
It is not recommended to drive with the P0128 code as it can lead to potential engine damage due to overheating or inefficient fuel consumption.
5. How can I repair the P0128 code in my Lexus?
Repair options may include replacing the thermostat, topping up coolant levels, fixing any leaks in the cooling system, or replacing the coolant temperature sensor.
6. How important is it to address the P0128 code promptly in a Lexus?
It is crucial to address the P0128 code promptly to prevent potential engine damage, ensure optimal engine performance, and maintain fuel efficiency.
7. Can a DIY enthusiast fix the P0128 code in a Lexus themselves?
Depending on the individual's mechanical skills and access to tools, some DIY enthusiasts may be able to address the P0128 code by following repair guides and instructions carefully.
8. Are there any preventive measures to avoid the P0128 code in a Lexus?
Regular maintenance of the cooling system, checking coolant levels, replacing the thermostat at recommended intervals, and addressing any cooling system issues promptly can help prevent the P0128 code from appearing.
9. Will resetting the OBDII system clear the P0128 code in a Lexus?
Resetting the OBDII system may temporarily clear the code, but if the underlying issue with the coolant thermostat is not addressed, the code is likely to reappear.
10. How long does it typically take to repair the P0128 code in a Lexus?
The repair time for the P0128 code can vary depending on the exact cause of the issue, but it may take anywhere from half an hour to a few hours to complete the necessary repairs.
Discuss the causes and fixes for P0128 Lexus OBDII Code
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There is a chance that the P0128 code could be trigger by a bad engine, but not for the transmission. If the engine is bad there will be other symptoms and codes, other than the P0128 code.
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Hello, my thermostat was stuck for it changed in September, now it is giving me the p0128 code and it started smoking I can’t leave it on for more than 3-4 minutes without it smoking .. I’m a single female and don’t want a mechanic to take advantage of me especially since a new thermostat was put ion it sept ... any help please! I’m trying to figure this out before taking it in so I know what to look out for
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Where is the smoke coming from? do you see any coolant leaks under your vehicle?
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