DTC 0902

SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the rear heated oxygen sensor heaters corresponding to the engine speed.




OPERATION




CONSULT REFERENCE VALUE IN DATA MONITOR MODE
Specification data are reference values.

Terminals 122 Thru 123:

ECM TERMINALS AND REFERENCE VALUE
Specification data are reference values and are measured between each terminal and 32 (ECM ground).




ON BOARD DIAGNOSIS LOGIC




DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 5 seconds before conducting the next test.

TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is between 10.5 V and 16 V at idle.

With Consult
1. Turn ignition switch "ON" and select "DATA MONITOR" mode with CONSULT.
2. Start engine.
3. Drive vehicle at a speed of more than 70 KPH (43 MPH) for 2 consecutive minutes.
4. Stop vehicle and let engine idle for at least 6 seconds.
5. If 1st trip DTC is detected, go to "Diagnostic Procedure".

With Generic Scan Tool
1. Start engine.
2. Drive vehicle at a speed of more than 70 KPH (43 MPH) for 2 consecutive minutes.
3. Stop vehicle and let engine idle for at least 6 seconds.
4. Turn ignition switch "OFF" and wait at least 5 seconds.
5. Start engine.
6. Drive vehicle at a speed of more than 70 KPH (43 MPH) for 2 consecutive minutes.
7. Stop vehicle and let engine idle for at least 6 seconds.
8. Select "MODE 3" with GST.
9. If DTC is detected, go to "Diagnostic Procedure".

Without Scan Tools
1. Start engine.
2. Drive vehicle at a speed of more than 70 KPH (43 MPH) for 2 consecutive minutes.
3. Stop vehicle and let engine idle for at least 6 seconds.
4. Turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
5. Perform "Diagnostic Test Mode II (Self-diagnostic results)" with ECM.
6. If 1st trip DTC is detected, go to "Diagnostic Procedure".
- When using GST, "DTC Confirmation Procedure" should be performed twice as much as when using CONSULT or ECM (Diagnostic Test Mode II) because GST cannot display MODE 7 (1st trip DTC) concerning this diagnosis. Therefore, using CONSULT or ECM (Diagnostic Test Mode II) is recommended.







WIRING DIAGRAM



















DIAGNOSTIC PROCEDURE







COMPONENT INSPECTION
Check the following.
1. Check resistance between terminals 2 and 3.
Resistance: 2.3 - 4.3 Ohm at 25 °C (77 °F)
2. Check continuity.
If NG, replace the rear heated oxygen sensor.

CAUTION: Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.