Toyota Corolla Repair Manual: Check open circuit
- 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.
- Check the resistance.
- 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.
- 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.
- Check the voltage.
- 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.
- 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.
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 pull–in 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 ...