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:
Manual air conditioning system
Air conditioning controls
The display and button positions will differ depending on the type of
the system.
Fan speed control switch
Temperature control switch
"MAX A/C" switch
"A/C" switch
Outside air mode switch
Recirculated air mode switch
Airflow mode control switch
Rear window defogge ...
Circuit inspection
1 Check d squib circuit(airbag sensor assy center – horn button
assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the airbag sensor
assy center and the horn button assy.
connect the ...
Using the radio (Multimedia system)
Radio operation
Select “AM” or “FM” on the audio source selection screen to begin listening
to the radio.
Audio control screen
Pressing the “AUDIO” button displays the audio control screen from any screens
of the selected source.
1 Audio source selection screen appears
2 Preset ...


