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 Inspect skid control ecu connector(+bs terminal voltage)
Disconnect the skid control ecu connector.
measure the voltage between terminals +bs (2) and gnd
(1, 23) of skid control ecu harness side connector.
Voltage: 10 – 14 v
2 Reconfirm dtc
Check the dtc .
Ok :
...
Brake fluid
Bleeding
Notice:
wash the brake fluid off immediately if it comes into contact with any painted
surface.
Hint:
if any work is done on the brake system or if air in the brake lines is
suspected, bleed the air from the system.
1. Fill reservoir with brake fluid
fluid: sae j1703 or fmvss no. ...
How to proceed with troubleshooting
1 Vehicle brought to workshop
2 Customer problem analysis
3 Problem symptom confirmation
4 Circuit inspection
5 Repair or replace
6 Confirmation test
7 End
Customer problem analysis check
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