
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 circuitRear coil spring
Components
Removal
Hint:
Use the same procedures for the rh side and lh side.
The procedures listed below are for the lh side.
Remove rear wheel
Remove skid control sensor wire (for 2wd)
(see page bc-198)
Remove rear speed sensor lh (for 4wd) (see
page bc-205)
Disconnect ...
Child restraint system
fixed with a seat belt
A child restraint system for a
small child or baby must itself be
properly restrained on the seat
with the lap portion of the
lap/shoulder belt.
â– Installing child restraint
system using a seat belt
(child restraint lock function
belt)
Install the child restraint system
in accordance to the operat ...
Fuel tank cap
Inspection
Inspect fuel tank cap assembly
Visually check that the cap and gasket are not
deformed or damaged.
If the result is not as specified, replace the cap
assembly or gasket.
Remove the gasket from the exhaust manifold.
...