Toyota Corolla (E120): Circuit description

The ignition switch provides circuit power and the ecm provides the circuit ground that illuminates the mil.

Mil operation is checked visually: it should be illuminated when the ignition is first turned on. If the mil is off all of the time or on all of the time, use the procedure below to troubleshoot it. The mil is used to indicate the ecm’s detection of a vehicle malfunction.

Follow this procedure using the hand–held tester or an obd ii scan tool to determine the cause of the problem and to check the mil.

Wiring diagram

Inspection procedure

    Share this page:

    Other materials:

    Inspection procedure
    1 Check security indicator light Remove the security indicator.  check the indicator light, as shown in the illustration and table. Standard: 2 Check wire harness (tvip ecu  security indicator) Disconnect the tvip ecu and security indicator connectors.   ...

    Check dlc3
    The vehicle’s ecm uses the iso 9141–2 for communication protocol. The terminal arrangement of the dlc3 complies with sae j1962 and matches the iso 9141–2 format. Hint: if the display shows unable to connect to vehicle when you have connected the cable of the obd ii scan tool or the h ...

    Front wheel alignment
    Adjustment 1. Inspect tire 2. Measure vehicle height Vehicle height: Measuring points: a: ground clearance of front wheel center b: ground clearance of lower suspension arm front bolt center c: ground clearance of axle beam set bolt center d: ground clearance of rear wheel center Not ...