
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
![]()

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 circuitRCTA function
â– Operation of the RCTA
function
The RCTA function uses rear
side radar sensors to detect
vehicles approaching from the right or left at the rear of the
vehicle and alerts the driver of
the presence of such vehicles
by flashing the outside rear view
mirror indicators and sounding a
buzzer.
Appr ...
If you have a flat tire
Your vehicle is equipped with a spare tire. The flat tire can be
replaced with the spare tire.
WARNING
â– If you have a flat tire
Do not continue driving with a flat tire.
Driving even a short distance with a flat tire can damage the tire and the
wheel beyond repair, which could result in an accide ...
Panoramic moon roof
Use the overhead switches
to operate the panoramic
moon roof and electronic
sunshade.
Operating the electronic
sunshade and panoramic
moon roof
â– Opening and closing the
electronic sunshade
Opens the electronic sunshade*
Slide and hold the switch
backward. The electronic sunshade
will fully ...