Check Open Circuit

CHECK OPEN CIRCUIT




a. For an open circuit in the wire harness in Fig. 1, perform a resistance check (step b) or a voltage check (step c).







b. Check the resistance.
1. Disconnect connectors A and C and measure the resistance between them.

HINT: Measure the resistance while lightly shaking the wire harness vertically and horizontally.

If you results match the examples above, an open circuit exists between terminal 1 of connector A and terminal 1 of connector C.







2. Disconnect connector B and measure the resistance between the connectors.
If your results match the examples above, an open circuit exists between terminal 1 of connector B2 and terminal 1 of connector C.




c. 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.

With each connector still connected, measure the voltage between the body ground and these terminals (in this order): 1) terminal 1 of connector A at the ECU 5 V output terminal, 2) terminal 1 of connector B, and 3) terminal 1 of connector C.




2. Example results:

If your results match the examples above, an open circuit exists in the wire harness between terminal 1 of connector B and terminal 1 of connector C.