
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 axle hub bolt
Components
Replacement
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 rear disc brake cylinder assembly
lh (see page br-55)
Remove rear disc (see page br-57)
Remove rear axle hub bolt
...
Driver side seat belt warning light does not operate
Description
When the ignition switch is on, the center airbag sensor transmits front seat
inner belt status signals to
the combination meter through the can bus line. If the driver seat belt is not
fastened, the combination
meter blinks the driver side seat belt warning light. If the seat bel ...
Reassembly
Caution:
Wear protective gloves. Sharp areas on the seat frame
(with adjuster) may injure your hands.
Install front seat wire
Install seat position airbag sensor (see
page rs-390)
Install lumbar support adjuster assembly
Install the lumbar support adjuster with the 2
screws.
...