Code 13 - Heated Oxygen Sensor Circuit

NOTE: See appropriate WIRING DIAGRAM in WIRING DIAGRAMS section for terminal and connector identification.

NOTE: Test numbers refer to numbers on diagnostic chart.

This step checks AIR system operation:
- Idle engine at normal operating temperature.
- Stop engine.
- Disconnect AIR hose at check valve and plug check valve.
- Restart engine and idle, immediately check direction of airflow.
This step tests continuity of oxygen sensor circuit (Green wire) between ECM 22-pin connector terminal No. 20 and oxygen sensor.

Fig 1: Code 13 - Diagnostic Flowchart (2.6L Passport)

Courtesy of ISUZU MOTOR CO.