
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 circuitCustomization
Customizable features
Your vehicle includes a variety of electronic features that can be
personalized to your preferences. The settings of these features
can be changed by using the steering wheel switches, entune
premium audio with navigation or entune audio, or at your
toyota dealer.
Customi ...
Wireless remote control
Function summary
The wireless remote control can be used to lock and unlock the vehicle.
It also opens and closes the back door.
Vehicles without a smart key system
Locks all the doors
Unlocks all the doors
Pressing the button unlocks the
driver’s door. Pressing the button
again wi ...
Rear axle hub bolt
Components
Replacement
Hint:
Use the same procedures for the rh side and lh side.
The procedures listed below are for the lh side.
Remove rear wheel
Remove rear disc brake cylinder assembly
lh (see page br-55)
Remove rear disc (see page br-57)
Remove rear axle hub bolt
...