
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 circuitUsing the aux port
This port can be used to connect a portable audio device and listen
to it using the vehicle’s speakers.
Open the cover and connect
the portable audio device.
Press the “media” button repeatedly until “aux” is displayed.
Silencing a sound
Press
(mute).
To cancel, p ...
Cleaning and protecting
the vehicle interior
The following procedures will help protect your vehicle’s interior
and keep it in top condition:
Protecting the vehicle interior
Remove dirt and dust using a vacuum cleaner. Wipe dirty surfaces
with a cloth dampened with lukewarm water.
Cleaning the leather areas
Remove dirt and dust usin ...
Components
...