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DTC P0030 HO2S HEATER CONTROL CIRCUIT (BANK 1 SENSOR 1)

DTC P0030 HO2S HEATER CONTROL CIRCUIT (BANK 1 SENSOR 1)

DTC DETECTING CONDITION:


• Two consecutive driving cycles with fault

• GENERAL DESCRIPTION


Important

After repair or replacement of faulty parts, conduct Clear Memory Mode and Inspection Mode .


WIRING DIAGRAM:


CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.

Start the engine and warm-up engine.

Turn the ignition switch to OFF.

Disconnect the connectors from ECM and front oxygen (A/F) sensor.

Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector.

Connector & terminal

(B134) No. 2 — (B18) No. 4:

(B134) No. 3 — (B18) No. 4:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between ECM and front oxygen (A/F) sensor connector.


CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.

Measure the resistance of harness between ECM and front oxygen (A/F) sensor connector.

Connector & terminal

(B134) No. 33 — (B18) No. 1:

(B134) No. 26 — (B18) No. 3:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between main relay and front oxygen (A/F) sensor connector.


CHECK HARNESS BETWEEN A/F AND OXYGEN SENSOR RELAY AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.

Measure the resistance of harness between main relay and front oxygen (A/F) sensor connector.

Connector & terminal

(B371) No. 11 — (B18) No. 6:

Is the resistance less than 1 Ω?

Yes


No

Repair the open circuit in harness between A/F and oxygen sensor relay and front oxygen (A/F) sensor connector.


CHECK FRONT OXYGEN (A/F) SENSOR.

Measure the resistance between front oxygen (A/F) sensor connector terminals.

Terminals

No. 3 — No. 4:

Is the resistance less than 5 Ω?

Yes


No

Replace the front oxygen (A/F) sensor.


CHECK POOR CONTACT.

Check the poor contact in ECM and front oxygen (A/F) sensor connector.

Is there poor contact in ECM or front oxygen (A/F) sensor connector?

Yes

Repair the poor contact in ECM or front oxygen (A/F) sensor connector.


No

Replace the front oxygen (A/F) sensor.