Toyota Corolla (E120): Check and replace ecu
Notice
: start an inspection of the connector from the backside of the connector on the wire harness side with the connector connected to the ecu.
When no measurement condition is specified, perform the inspection with the engine stopped and also the ignition switch on.
- First check the ecu ground circuit. If it is faulty, repair it.
If it is normal, the ecu could be faulty. In this case, replace the ecu with one that functions normally and check if the symptoms appear.
- Measure the resistance between the ecu ground
terminal and body ground.
Resistance: 1 Ω or less

- Disconnect the ecu connector, check the ground terminals on the ecu side and wire harness side for bends and check the contact pressure.

Other materials:
Replacement
1. Work for preventing gasoline from spilling out
2. Remove front wheels
3. Remove engine under cover rh
4. Remove engine under cover lh
5. Drain coolant
6. Remove cylinder head cover no.2
Remove the 2 nuts, 2 clips and cylinder head cover.
7. Disconnect radiator hose inlet
&nb ...
Other functions
■ Switching between outside air and recirculated air modes
Press .
The mode switches between outside air mode (indicator off) and recirculated air
mode (indicator on) each time is pressed.
■ Defogging the windshield
Defoggers are used to defog the windshield and front side w ...
Data list/active test
1. Data list
Hint:
according to the data list displayed by the obd ii scan tool or hand–held
tester, you can read the value
of the switch, sensor, actuator and so on without parts removal. Reading the
data list as the first step of
troubleshooting is one method to shorten labor time.
W ...


