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:
Phone screen
To display the screen shown below, press the
switch on the steering wheel or the
button.
Several functions are available to operate on each screen that is displayed by
selecting the 4 tabs.
1 Device name
2 Bluetooth® connection status
■ Telephone switch
■ Microphone
υ ...
Inspection
1. Inspect front seat inner belt assy lh
When fastening the seat belt (buckle switch on).
Inspect the continuity and resistance between the
terminals.
Standard:
If the result is not as specified, replace the inner belt.
When releasing the seat belt (buckle switch ...
If your vehicle overheats
The following may indicate that your vehicle is overheating.
● Vehicles without a multi-information display: The high engine coolant temperature
warning light comes on or a loss of power is experienced.
Vehicles with a multi-information display: The engine coolant temperature gauge&n ...


