
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 circuitCanceling and resuming
the speed control
Pressing the cancel switch
cancels the speed control.
The speed control is also canceled
when the brake pedal is depressed.
(When the vehicle has been
stopped by system control,
depressing the brake pedal does
not cancel the setting.)
Pressing the "+RES" switch
resumes the cruise control
a ...
Settings display
Vehicle settings and the content
displayed on the screen can be
changed by using the meter
control switches.
â– Setting procedure
1. Press and hold to display
the cursor on the content display
area (center).
2. Press or
with the cursor
on the content display
area (center) to select
and then pre ...
Inspection
Inspect rear stabilizer link assembly lh
As shown in the illustration, move the ball joint stud
back and forth 5 times before installing the nut.
Using a torque wrench, turn the nut continuously at
a rate of 3 to 5 seconds per turn and take the torque
reading on the fifth turn.
...