
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 circuitDrl relay circuit
Description
The main body ecu controls the daytime running light no. 2 Relay (marking:
drl no.2).
Wiring diagram
Inspection procedure
Inspect daytime running light relay (marking: drl no. 2, Drl no. 3,
Drl no. 4)
Remove the no. 2 Relay, no. 3 Relay and no. 4 Relay from
th ...
Removal
(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).
Drain the automatic transaxle fluid for u151f (see
page ax-173).
Remove front axle hub nut ( ...
Installation
(2005/11-2006/01)
Install front drive shaft assembly lh
Coat the spline of the inboard joint shaft with gear
oil.
Using a brass bar and hammer, align the shaft
splines in the drive shaft.
Notice:
Set the snap ring with the opening side facing
downwards.
Be careful not to damage the oil s ...