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:
What to do if... (Troubleshooting)
If there is a problem with the hands-free system or a Bluetooth® device, first
check the table below.
► When using the hands-free system with a
Bluetooth® device
► When registering/connecting a cellular
phone
► When making/receiving a call
► When using the p ...
Replacement
1. Drain brake fluid
Notice:
wash the brake fluid off immediately if it comes into contact with any painted
surface.
2. Remove front wheel rh
3. Remove front fender liner rh
4. Remove brake actuator with bracket
turn the latch of the actuator connector to disconnect the
connector. ...
Inspection procedure
Hint:
read freeze frame data using the hand-held tester or the obd ii scan tool.
Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, it is
useful for determining whether
the vehicle was running or stopped, the engine was warmed up or not, the ...


