
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 circuitOn-vehicle inspection
Check camshaft timing oil control valve
assembly
Check the operation.
Connect the intelligent tester to the dlc3.
Turn the ignition switch on.
Turn the intelligent tester main switch on.
Start and warm up the engine.
Select the menu items: diagnosis /
enhanced obd ii / ...
Check mode procedure
Panel diagnosis (indicator check)
Turn the ignition switch to lock.
Turn the ignition switch on while simultaneously
pressing the a/c control auto switch and the rec/
frs switch.
Check that all indicators and the display area are
turned on and off 4 times in succession at 1 second ...
Installation
Install upper instrument panel
Attach the 6 clips and 5 claws to install the
instrument panel.
Connect the connectors and clamps.
Install the 2 bolts and 2 screws.
Connect the passenger airbag connector.
Install the 2 bolts to the passenger airbag.
Torque: 20 n*m (204 k ...