Toyota Tacoma manuals

Toyota Corolla Repair Manual: 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

Basic inspection
Resistance measuring condition of electronic parts  unless stated, all resistance is measured at an ambient temperature of 20 c (68 F). As the resistance may be outside the specifi ...

Check short circuit
If the wire harness is ground shorted as shown in fig. 5, Locate the section by conducting a resistance check with the body ground in step (b). Check the resistance with the body grou ...

Other materials:

Inspection procedure
1 Inspect cruise control actuator assy Turn the ignition switch to off.  disconnect the cruise control actuator assy connector.  measure the resistance between terminals 1 (mo) and 2 (mc) of cruise control actuator assy. Hint: if control plate position is fully opened or ...

Starting system
Inspection 1. Inspect starter assy Notice: these tests must be performed within 3 to 5 seconds to prevent burnout of the coil.  perform the pullin test.  Remove the nut, then disconnect the lead wire from terminal c. Connect the battery to the starter repair ...

Windshield wiper switch assy
Replacement 1. Remove steering column cover lwr Remove 3 screws and steering column cover lwr. 2. Remove windshield wiper switch assy Disconnect the connecter of the windshield wiper switch.  release the claw and pull out the windshield wiper switch assy as shown in the ...

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