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:
Circuit description
The rotary solenoid type idle air control (iac) valve is located
under the throttle body and intake air bypassing the throttle
valve flows into the iac valve through the passage.
In this way the intake air volume bypassing the throttle valve is
regulated, controls the engine speed.
The ...
How to proceed with troubleshooting
1 Vehicle brought to workshop
2 Customer problem analysis
3 Check and clear dtc
4 Problem symptom confirmation
5 Symptom simulation
6 Dtc check
7 Dtc chart
8 Problem symptoms table
9 Circuit inspection
10 Identification of problem
11 Parts inspection
12 Repair
1 ...
Clock assy
Replacement
1. Remove console panel upper
2. Remove heater control knob
3. Remove instrument cluster finish panel
4. Remove clock assy
Using a screwdriver, disengage the 4 claws, remove the
clock as shown in the illustration.
Hint:
tape the screwdriver tip before use. ...


