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 procedure
1 Check door lock
2 Check wire harness (tvip ecu door lock)
Disconnect the tvip ecu and door lock connectors.
check the continuity between the terminals of the tvip
ecu and door lock connectors, as shown in the illustration
and table.
Standard:
3 Check wire harness ...
Check open circuit
For the open circuit in the wire harness in fig. 1, Perform
a resistance check in step (b) or a voltage check in step
(c) to locate the section.
Check the resistance.
Disconnect connectors a and c and measure the
resistance between them.
Resistance: 1 Ω or les ...
Warning lights and indicators
The warning lights and indicators on the instrument cluster,
center panel, overhead console and outside rear view mirrors inform the driver
of the status of the vehicle's various systems.
Warning lights and indicators displayed on the instrument
cluster
For the purpose of explanation, the followin ...


