
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 circuitDiagnostic trouble code chart (2006/01- )
Hint:
When the air conditioning system functions properly, dtc
b1400/00 is output.
Hint:
*1: Dtc b1422/22 (compressor lock sensor circuit) is
indicated only for a currently occurring malfunction for 2grfe.
*2: Compressor and pulley for 2az-fe, compressor and
magnetic clutch for 2gr-fe ...
Stuck in deceleration sensor
Description
The skid control ecu receives signals from the yaw rate and deceleration
sensor via the can
communication system.
The yaw rate sensor has a built-in deceleration sensor and detects the vehicle's
condition using 2 circuits
(gl1: g sensor 1, gl2: g sensor 2).
If there is t ...
Only rear door lh lock / unlock functions do not operate
Description
The main body ecu receives lock / unlock switch signals and activates the
door lock motor accordingly.
Wiring diagram
Inspection procedure
Inspect rear door with motor lock assembly lh
Apply the battery voltage to the door lock motor and
check the operation of th ...