Corolla LE Sedan L4-1.8L (1ZZ-FE) (1999)
Between terminal 1 of connector "A" and terminal 1 of connector "C" -> No continuity (open).
Between terminal 2 of connector "A" and terminal 2 of connector "C" -> Continuity.
Therefore, it is found out that there is an open circuit between terminal 1 of connector "A" and terminal 1 of connector "C".
2. 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" -> Continuity.
Between terminal 1 of connector "B2" and terminal 1 of connector "C" -> No continuity (open).
Therefore, it is found out that there is an open circuit between terminal 1 of connector "B2" and terminal 1 of connector "C".
B. Check the voltage.
In a circuit in which voltage is applied (to the ECU connector terminal), an open circuit can be checked for by conducting a voltage check.
Figure 4
As shown in Fig. 4, with each connector still connected, measure the voltage between body ground and terminal 1 of connector "A" at the ECU 5V
out-put terminal, terminal 1 of connector "B", and terminal 1 of connector "C", in that order.
If the results are:
5V: Between Terminal 1 of connector "A" and Body Ground
5V: Between Terminal 1 of connector "B" and Body Ground
OV: Between Terminal 1 of connector "C" and Body Ground
Then it is found out that there is an open circuit in the wire harness between terminal 1 of "B" and terminal 1 of "C".
7. CHECK SHORT CIRCUIT
Figure 5
If the wire harness is ground shorted as in Fig. 5, locate the section by conducting a "continuity check with ground".