
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
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Install fuel filler opening lid lock retainer
Install the lock retainer and turn it counterclockwise
as shown in the illustration.
Install fuel filler opening lid lock retainer
Install the cable and turn it clockwise as shown in
the illustration.
Install the fuel l ...
List screen operation
When a list screen is displayed, use the appropriate buttons to
scroll through the list.
How to scroll
Select to scroll to the next
or previous page.
Appears to the right of
titles, the complete titles are
too long for the display. Select
this button to scroll the title.
Turn th ...
Brake booster
Installation
(2005/11-2006/01)
Install check valve grommet
Install the grommet to the booster.
Install brake vacuum check valve
assembly
Install the check valve to the grommet.
Install brake booster gasket
Install a new gasket to the booster.
Install brake ...