
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 circuitChanging the display
The multi-information display is
operated using the meter control
switches.
Scroll the screen*/switch the
display*/move the cursor
Press: Enter/Set
Press and hold: Reset/Display
customizable items
Return to the previous screen
Call sending/receiving and
history display (if equipped)
Linke ...
How to proceed with troubleshooting (2005/11-2006/01)
Hint:
Use these procedures to troubleshoot the air conditioning
system.
*: Use the intelligent tester.
Vehicle brought to workshop
Customer problem analysis and symptom check
Inspect battery voltage
Standard voltage:
11 to 14 v
If the voltage is below 11 v, rechar ...
Usb port/aux port
Connect an ipod, usb memory device or portable audio player
to the usb/aux port as indicated below. Select “ipod�, “usb� or
“aux� on the audio source selection screen and the device can
be operated via audio system.
Connecting using the usb/aux port
Ipod
Open the cover and connect ...