Toyota Corolla (E120): Fail–safe chart
If any of the following codes is recorded, the ecm enters the fail–safe mode.

Check for intermittent problems
Hand–held tester only:
by putting the vehicle’s ecm in the check mode, the 1 trip detection logic is possible instead of the 2 trip detection logic, and the sensitivity to detect faults is increased. This makes it easier to detect intermittent problems.
- Clear the dtcs .
- set the check mode .
- perform a simulation test .
- check the connector and terminal .
- wiggle the harness and connector
Other materials:
Circuit description
If the engine coolant temperature (ect) does not reach 75°c (167°f) despite
sufficient warm – up time has
elapsed.
Dtc no
Dtc detection condition
Trouble area
P0128
Condition (a), (b) and (c):
cold start
after engine is warmed up
& ...
Refueling
Opening the fuel tank cap
Perform the following steps to open the fuel tank cap:
Before refueling the vehicle
● Close all the doors and windows, and turn the engine switch off.
● Confirm the type of fuel.
■Fuel types
Unleaded gasoline (Octane rating 87 [Research Octane Number ...
Circuit description
Shifting from 1st to o/d is performed in combination with on and off of the
shift solenoid valve s1 and s2
controlled by ecm. If an open or short circuit occurs in either of the solenoid
valves, the ecm controls the
remaining normal solenoid valve to allow the vehicle to be operated smoothly
...


