Toyota Corolla (E120): Check open circuit

  1. For the open circuit in the wire harness in fig. 1, Perform a resistance check in step (b) or a voltage check in step (c) to locate the section.

  1. Check the resistance.
  1.  Disconnect connectors a and c and measure the resistance between them.

    Resistance: 1 Ω or less

Hint

: measure the resistance while lightly shaking the wire harness vertically and horizontally. In the case of fig. 2: Between terminal 1 of connector a and terminal 1 of connector c " 10 kΩ

or higher between terminal 2 of connector a and terminal 2 of connector c " below 1 Ω

therefore, the cause is an open circuit between terminal 1 of connector a and terminal 1 of connector c.

  1. Disconnect connector b and measure the resistance between the connectors.

    In the case of fig. 3: Between terminal 1 of connector a and terminal 1 of connector b1 " below 1 w between terminal 1 of connector b2 and terminal 1 of connector c " 10 kw therefore, the cause is an open circuit between terminal 1 of connector b2 and terminal 1 of connector c.

  1. Check the voltage.
  1.  In a circuit in which voltage is applied (to the ecu connector terminal), an open circuit can be checked by conducting a voltage check.

    As shown in fig. 4, With each connector still connected, measure the voltage between the body ground and terminal 1 of connector a at the ecu 5 v output terminal, terminal 1 of connector b, and terminal 1 of connector c, in that order.

  2.  If the results are: 5 v: between terminal 1 of connector a and body ground 5 v: between terminal 1 of connector b and body ground 0 v: between terminal 1 of connector c and body ground therefore, the cause is an open circuit in the wire harness between terminal 1 of connector b and terminal 1 of connector c.

Check short circuit

    Share this page:

    Other materials:

    Starting the engine
    1 Check that the parking brake is set. ► Vehicles without a multi-information display 2 Continuously variable transmission: Check that the shift lever is set in P. Firmly depress the brake pedal. Manual transmission: Check that the shift lever is set in N. Firmly depress the clutch peda ...

    Adjustment
    Hint: in the rh side, work in the same procedure as in the lh side. Since the centering bolt is used as a door side hinge bolt, the door hinge cannot be adjusted with it on. Substitute the bolt with washer for the centering bolt. 1. Inspect front door panel sub–assy lh Che ...

    Manual shifting test
    1. Perform manual shifting test Hint: by this test, it can be determined whether the trouble is within the electrical circuit or is a mechanical problem in the transaxle. Disconnect the transmission wire connector.  inspect the manual driving operation. Check that the shift and g ...