
Hint:
This dtc relates to the thermostat.
Description
This dtc is set when the engine coolant temperature (ect) does not reach 75°c (167°f) despite sufficient engine warm-up time having elapsed.

Monitor description

The ecm estimates the ect based on the starting temperature, engine loads, and engine speeds. The ecm then compares the estimated temperature with the actual ect. When the estimated ect reaches 75°c (167°f), the ecm checks the actual ect. If the actual ect is less than 75°c (167°f), the ecm interprets this as a malfunction in the thermostat or the engine cooling system and sets the dtc.
Monitor strategy
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Typical enabling conditions

Typical malfunction thresholds

Inspection procedure
Hint:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

Hint:
If any dtcs other than p0128 are output, troubleshoot those dtcs first.


Standard value: 80 to 84°c (176 to 183°f)
Hint:
In addition to the above check, confirm that the valve is completely closed when the temperature is below the standard.

Insufficient coolant temperature for closed loop fuel control
Oxygen sensor circuitBluetooth® phone
settings
You can adjust the hands-free system to your desired settings.
“Phone/message settings” screen
To display the screen shown below, press the “setup” button, and
select “phone” on the “setup” screen.
Set the phone connection
Setting the sound
Contact/call history settings
...
How to proceed with troubleshooting (2005/11-2006/01)
Hint:
Use these procedures to troubleshoot the air conditioning
system.
*: Use the intelligent tester.
Vehicle brought to workshop
Customer problem analysis and symptom check
Inspect battery voltage
Standard voltage:
11 to 14 v
If the voltage is below 11 v, recha ...
Engine
On-vehicle inspection
Inspect engine coolant
Inspect engine oil
Inspect battery
Inspect air cleaner filter element subassembly
Remove the air cleaner cap.
Remove the air filter element.
Visually check that the air filter is not excessively
damaged or oily.
If necessary, rep ...