
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 circuitInstallation
Install knock sensor
Install the sensor with the nut.
Torque: 20 n*m (205 kgf*cm, 15 ft.*Lbf)
Notice:
Make sure that the knock sensor is in the
correct position.
Connect the sensor connector.
Install intake manifold insulator
install the intake manifold insulat ...
Rear differential side gear shaft oil seal
Components
Removal
Drain differential oil (see page df-10)
Remove tailpipe assembly
Remove the tailpipe (see page ex-2).
Remove center exhaust assembly
Remove propeller with center bearing
shaft assembly (see page pr-3)
Remove rear differential carrier subassembl ...
Setup menu
You can adjust the audio system to your desired settings.
Display “setup� screen
Press the “setup� button to display the “setup� screen.
Select to adjust the settings for
operation sounds, screen animation,
etc.
Select to display the voice settings
screen.
Select to adjus ...