DTC P0030: A/F/O2 Heater Control Circuit Bank 1 Sensor 1: Notes
DTC detecting condition:
Detected when two consecutive driving cycles with fault occur.
- After servicing or replacing faulty parts, perform Clear Memory Mode Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>CLEAR MEMORY MODE>OPERATION , and inspection mode Refer to ENGINE (DIAGNOSTICS) (EXCEPT FOR STI)>INSPECTION MODE>PROCEDURE ..
- Use the check board when measuring the ECM terminal voltage and resistance.
Wiring diagram:
Engine Electrical System Refer to WIRING SYSTEM>ENGINE ELECTRICAL SYSTEM>WIRING DIAGRAM .
- CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.
- Start and warm up the engine.
- Turn the ignition switch to OFF.
- Disconnect the connector from ECM.
- Disconnect the connectors from front oxygen (A/F) sensor.
- Measure the resistance of harness between ECM connector and front oxygen (A/F) sensor connector.
Connector & terminal
(E158) No. 15 - (E24) No. 1:
(E159) No. 9 - (E24) No. 2:
(E158) No. 27 - (E24) No. 4:
(E158) No. 39 - (E24) No. 5:
Is the resistance less than 1 Ω?
Yes: Go to 2.
No: Repair the open circuit of harness between ECM connector and front oxygen (A/F) sensor connector.
- CHECK FRONT OXYGEN (A/F) SENSOR.
Measure the resistance between front oxygen (A/F) sensor terminals.
Terminals
No. 2 - No. 3:
Is the resistance 2 - 3 Ω?
Yes: Go to 3.
No: Replace the front oxygen (A/F) sensor. Refer to FUEL INJECTION (FUEL SYSTEMS) (EXCEPT FOR STI)>FRONT OXYGEN (A/F) SENSOR .
- CHECK FOR POOR CONTACT.
Check for poor contact of ECM and front oxygen (A/F) sensor connector.
Is there poor contact of ECM or front oxygen (A/F) sensor connector?
Yes: Repair the poor contact of ECM or front oxygen (A/F) sensor connector.
No: Replace the front oxygen (A/F) sensor. Refer to FUEL INJECTION (FUEL SYSTEMS) (EXCEPT FOR STI)>FRONT OXYGEN (A/F) SENSOR .