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:

    Overhaul
    1. Inspect 1st gear thrust clearance Using a feeler gauge, measure the 1st gear thrust clearance. Standard clearance: 0.10 – 0.40 Mm (0.0039 – 0.0157 In.) 2. Inspect 2nd gear thrust clearance Using a dial indicator, measure the 2nd gear thrust clearance. Standard clearan ...

    Display and menu icons
    ■ Display Content display area By selecting menu icons on the multi-information display, a variety of driving-related information can be displayed. The multi-information display can also be used to change display settings and other vehicle settings. Warning or advice pop-up displays are also ...

    Circuit description
    A flat type knock sensor (non–resonant type) has the structure that can detect the vibration in a wider band of frequency from about 6 khz to 15 khz and has the following features. Knock sensors are fitted on the cylinder block to detect the engine knocking. The sensor contains a piezoele ...