1) Turn the ignition switch to OFF.
2) Disconnect the connectors from the ECM.
3) Measure the resistance between ECM and oxygen sensor connector.
Connector & terminal
(B136) No. 4 — (T6) No. 1:
Is the resistance less than 1 Ω?
Repair the harness and connector.
NOTE:
In this case, repair the following items.
• Open circuit of harness between the ECM and rear oxygen sensor
• Poor contact of coupling connector