Toyota Corolla (E120): Circuit description
If the engine coolant temperature (ect) does not reach 75°c (167°f) despite sufficient warm – up time has elapsed.
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Dtc no |
Dtc detection condition |
Trouble area |
| P0128 | Condition (a), (b) and (c):
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Monitor description

The ecm estimates the engine coolant temperature (ect) based on starting temperature, engine loads, and engine speeds. The ecm then compares the estimated ect 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 will interpret this as a fault in the thermostat or engine cooling system or thermostat and set a dtc.
Monitor strategy

Typical enabling conditions

Typical malfunction thresholds

Component operating range

Monitor result (mode 06 data)

Refer to page 05–27 for the detailed information on checking monitor status.
Other materials:
Cruise control
The vehicle can be driven at
a set speed even if the
accelerator pedal is not
depressed.
Use the cruise control only
on highways and expressways.
WARNING
■For safe use
Driving safely is solely the
responsibility of the driver.
Therefore, do not overly rely on
this system. The driver is solel ...
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The RSA system detects
specific road signs using
the front camera and/or navigation
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limit information is available)
and warns the driver
via displays and buzzers.
WARNING
■For safe use
Driving safely is solely the
responsibility of the driver. Pay
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Inspection procedure
1 Inspect shift solenoid valve(s1)
Remove the shift solenoid valve s1.
measure the resistance according to the value(s) in the
table below.
Standard:
Connect the positive (+) battery lead to the solenoid connector
terminal, and the negative (–) battery lead to the
solenoid ...


