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.

  1. 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.

  1.  Measure the resistance between the ecu ground terminal and body ground.

    Resistance: 1 Ω or less

  1. Disconnect the ecu connector, check the ground terminals on the ecu side and wire harness side for bends and check the contact pressure.

Terms

    Share this page:

    Other materials:

    How to proceed with troubleshooting
    The hand–held tester can be used at step 3, 4, 6, 9. 1 Vehicle brought to workshop 2 Customer problem analysis 3 Connect the obd ii scan tool or hand–held tester to dlc3 4 Check and clear dtc and freeze frame data 5 Visual inspection 6 Setting the check mode diagnosis 7 Proble ...

    Speed control main switch assy
    Replacement 1. Disconnect battery negative terminal 2. Inspect place front wheels facing straight ahead 3. Remove horn button assy 4. Remove steering wheel assy sst 09950–50013 (09951–05010, 09952–05010, 09953–05020, 09954–05021) 5. Remove speed control main switch assy Remov ...

    Inspection procedure
    1 Check p/t squib(rh) circuit(airbag sensor assy center – front seat outer belt assy rh) 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 seat belt pretensio ...