
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 circuitInstallation (2006/01- )
Install abs and traction actuator assembly with bracket
Notice:
do not remove the hole plug before connecting the
brake tube. new actuators are filled with brake fluid.
Install the actuator with bracket with the 3 nuts.
Torque: 19 n*m (194 kgf*cm, 14 ft.*Lbf)
Hint:
The nuts should b ...
Brk relay
On-vehicle inspection
Inspect brk relay
Remove the brk relay from the engine room no. 1
Relay block.
Measure the resistance of the relay.
Standard resistance
If the result is not as specified, replace the relay. ...
Dtc check / clear
Check dtc
When using intelligent tester:
Connect the intelligent tester (with can vim) to
the dlc3.
Turn the ignition switch on and press the
intelligent tester main switch on.
Read the dtcs by following the prompts on the
intelligent tester.
Hint:
Refer to the intel ...