
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 circuitChild restraint systems
Before installing a child
restraint system in the vehicle,
there are precautions
that need to be observed,
different types of child
restraint systems, as well as
installation methods, etc.,
written in this manual.
Use a child restraint system
when riding with a small child
that cannot properly use a ...
Removal
(2005/11-2006/01)
Remove front wheel
Drain automatic transaxle fluid
Drain the automatic transaxle fluid for u140f (see
page ax-147).
Drain the automatic transaxle fluid for u241e (see
page ax-146).
Remove front axle hub nut (see page ah-6)
Disconnect front speed sensor lh (see page
bc-191) ...
Data list / active test
Read data list
Hint:
Using the intelligent tester's data list allows switch,
sensor, actuator, and other item values to be read
without removing any parts. Reading the data list
early in troubleshooting is one way to save time.
Notice:
In the table below, the values listed under "no ...