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:
Inspection and adjustment procedure
1 Tire valve
2 Tire pressure gauge
1 Remove the tire valve cap.
2 Press the tip of the tire pressure gauge onto the tire valve.
3 Read the pressure using the gauge gradations.
4 If the tire inflation pressure is not at the recommended level, adjust the pressure.
If you add too much air, pres ...
Inspection procedure
1 Check p squib circuit(airbag sensor assy center – instrument
panel passenger airbag 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 instrument panel ...
Circuit description
The throttle position sensor is mounted in the throttle body and
detects the throttle valve opening angle.
When the throttle valve is fully closed, a voltage of approximately
0.3 To 1.0 V is applied to terminal vta of the ecm. The voltage
applied to terminal vta of the ecm increases in pro ...


