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:
Wireless remote control
(if equipped)
The keys are equipped with the
following wireless remote control:
Vehicles without a smart key
system
Locks the doors
Unlocks the doors
Opens the windows*1 and
moon roof*1, 2
Opens the trunk
Sounds the alarm
Vehicles with a smart key system
Locks the doors
Unlocks the doors
Opens the ...
How to use this manual
1. Body panel replacement in this manual
2. Symbols
3. Illustration of weld point symbols
...
Inspection procedure
1 Check voltage at ig2 of airbag sensor assy center
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connector of the airbag sensor assy center.
connect the negative (–) terminal cable to the battery,
and wa ...


