
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 circuitPKSB (Parking Support
Brake)
The Parking Support Brake
system consists of the following
functions that operate
when driving at a low
speed or backing up, such
as when parking. When the
system determines that the
possibility of a collision
with a detected object is
high, a warning operates to
urge the driver to take evasive
acti ...
Fuel information
You must only use unleaded
gasoline in your vehicle.
Select octane rating 87
(Research Octane Number
91) or higher. Use of
unleaded gasoline with an
octane rating lower than 87
may result in engine knocking.
Persistent knocking
can lead to engine damage.
At minimum, the gasoline you
use should meet ...
On-vehicle inspection
Check camshaft timing oil control valve
assembly
Check the operation.
Connect the intelligent tester to the dlc3.
Turn the ignition switch on.
Turn the intelligent tester main switch on.
Start and warm up the engine.
Select the menu items: diagnosis /
enhanced obd ii / ...