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
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.
Reassembly
Hint:
When installing the ornament plate and emblem, heat the
radiator grille, ornament plate and emblem using a heat light.
Standard heating temperature
Notice:
Do not heat the emblem base and emblem excessively.
Install radiator grille emblem
Attach the 4 claws to install the radi ...
Air inlet damper control servo motor circuit
Description
The damper servo (air inlet control) sends pulse signals to indicate the
damper position to the air
conditioning amplifier. The air conditioning amplifier activates the motor
(normal or reverse) based on
these signals to move the air inlet control damper to the appropriate pos ...
Downhill assist control indicator light does not come on
Description
Refer to the description of "downhill assist control indicator light remains
on" (see page bc-156).
Wiring diagram
Refer to the downhill assist control indicator light circuit (see page
bc-157).
Inspection procedure
Check can communication system
Check if the ...