
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 circuitIntake air temperature sensor gradient too high
Description
The intake air temperature (iat) sensor, mounted on the mass air flow (maf)
meter, monitors the iat.
The iat sensor has a built-in thermistor with a resistance that varies according
to the temperature of the
intake air. When the iat is low, the resistance of the thermist ...
Dtc check / clear
Check dtc
Hint:
When dtc b1650/23 is detected as a result of
troubleshooting for the airbag system, troubleshoot
the occupant classification system.
Use the intelligent tester (with can vim) to read and
clear dtcs, otherwise the dtcs cannot be read and
cleared.
Connect ...
Camshaft position "A"
Dtc P0011 Camshaft position
"a" - timing over-advanced or system performance (bank 1)
Dtc P0012 Camshaft
position "a" - timing over-retarded (bank 1)
Description
The vvt system includes the ecm, oil control valve (ocv) and vvt controller.
The ecm sends a target
du ...