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:

    Fuel information
    You must only use unleaded gasoline in your vehicle. Select octane rating 87 (Research Octane Number 91) or higher. Use of unleaded gasoline with an octane rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage. At minimum, the gasoline you use should ...

    Inspection procedure
    Hint: read freeze frame data using the hand-held tester or the obd ii scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the ...

    Engine oil
    With the engine at operating temperature and turned off, check the oil level on the dipstick. ■ Checking the engine oil 1 Park the vehicle on level ground. After warming up the engine and turning it off, wait more than 5 minutes for the oil to drain back into the bottom of the engine. 2 ...