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:
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 ...
Overhaul
1. Remove oil pump relief valve
Remove the oil pump relief valve plug, oil pump relief
valve spring and oil pump relief valve.
Oil pump relief valve plug
oil pump relief valve spring
oil pump relief valve
2. Inspect oil pump assy
Remove 3 screws and o ...
Manual air conditioning system∗
Air conditioning controls
► Heater
► Air conditioning system
■ Adjusting the temperature setting
► Heater
To adjust the temperature setting, turn the
dial clockwise to increase the temperature.
► Air conditioning system
To adjust the temperature setting, tu ...


