
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 circuitGauges and meters (with 12.3-inch multi-information display)
The meters display various drive information.
Meter display
â– Locations of gauges and meters
The meter type can be changed on
of the multi-information display.
Type 1/Type 2
The units of measure may differ depending on the intended destination of
the vehicle.
Multi-information display
Presen ...
Diaphragm oil seal
Components
Removal
Drain differential oil
Using a 10 mm socket hexagon wrench, remove the
rear differential drain plug and gasket, and drain the
oil.
Install a new gasket to the rear differential drain
plug.
Using a 10 mm socket hexagon wrench, install the
rear differe ...
Key lock-in prevention function does not work properly
Description
When the key is in the ignition key cylinder or the door courtesy light on
signal is output to the main body
ecu, performing the door lock operation with the lock switch does not lock the
door.
Wiring diagram
Inspection procedure
Read value of intelligent tester (unlock w ...