ENGINE (DIAGNOSTICS)(H4DO) > Diagnostic Procedure with Diagnostic Trouble Code (DTC)
DTC P0134 A/F / O2 SENSOR CIRCUIT NO ACTIVITY DETECTED BANK 1 SENSOR 1
DTC detecting condition:
Immediately at fault recognition
CAUTION:
After servicing or replacing faulty parts, perform Clear Memory Mode Clear Memory Mode > OPERATION">
, and Inspection Mode Inspection Mode > PROCEDURE">
.
Wiring diagram:
Engine electrical system Engine Electrical System">

| STEP | CHECK | YES | NO |
1.CHECK HARNESS BETWEEN ECM AND FRONT OXYGEN (A/F) SENSOR CONNECTOR.
1) Turn the ignition switch to OFF.
2) Disconnect the connector from ECM.
3) Disconnect the connectors from front oxygen (A/F) sensor.
4) Measure the resistance of harness between ECM connector and front oxygen (A/F) sensor connector.
Connector & terminal
(B136) No. 19 — (E24) No. 3:
(B136) No. 18 — (E24) No. 4:
Is the resistance less than 1 ??
Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P0134 A/F / O2 SENSOR CIRCUIT NO ACTIVITY DETECTED BANK 1 SENSOR 1">Go to Step 2.
Repair the harness and connector.
NOTE:
In this case, repair the following item:
• Open circuit in harness between ECM connector and front oxygen (A/F) sensor connector
• Poor contact of coupling connector
2.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?
Repair the poor contact of ECM or front oxygen (A/F) sensor connector.
Replace the front oxygen (A/F) sensor. Front Oxygen (A/F) Sensor">
1. OUTLINE OF DIAGNOSIS
Detect open circuits of the sensor.
Judge as NG when the impedance of the element is large.
2. COMPONENT DESCRIPTION

(A) | Electromotive force | (B) | Air fuel ratio | (C) | Rich |
(D) | Lean | ||||
(1) | Exhaust gas | (2) | Zirconia element oxygen |
3. EXECUTION CONDITION
Secondary Parameters | Execution condition |
Battery voltage | ≥ 10.9 V |
Time of heater control duty at 70 % or more | ≥ 36000 ms |
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
5. DIAGNOSTIC METHOD
If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.
Malfunction Criteria | Threshold Value |
Front oxygen (A/F) sensor impedance | > 450 ? |
Time Needed for Diagnosis: 5000 ms
Malfunction Indicator Light Illumination: Illuminates as soon as a malfunction occurs.
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