P0135

SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the front heated oxygen sensor heater corresponding to the engine conditions.

Engine Speed (rpm) / Front heated oxygen sensor heater
Above 4,400 / OFF
Below 4,400 / ON




DIAGNOSTIC TROUBLE CODE CONFIRMATION PROCEDURE

With Consult
(1) Turn ignition switch "ON" and select "DATA MONITOR" mode with CONSULT.
(2) Start engine and run it for at least 5 seconds at idle speed.

OR

With GST
(1) Start engine and run it for at least 5 seconds at idle speed.
(2) Turn ignition switch "OFF" and wait at least 5 seconds.
(3) Start engine and run it for at least 5 seconds at idle speed.
(4) Select "MODE 3" with GST.

OR

No Tools
(1) Start engine and run it for at least 5 seconds at idle speed.
(2) Turn ignition switch "OFF", wait at least 5 seconds and then turn "ON".
(3) Perform "Diagnostic Test Mode II" (Self-diagnostic results) with ECM.
- When using GST, "DIAGNOSTIC TROUBLE CODE 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.

EC-FRO2/H-01 Front Heated Oxygen Sensor Heater (DTC P0135):

WIRING DIAGRAM




DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION
Front Heated Oxygen Sensor Heater




Check resistance between terminals (3) and (1).

Resistance: 2.3 - 4.3 Ohms at 25°C (77°F)

Check continuity between terminals (2) and (1), (3) and (2).
Continuity should not exist.
If NG, replace the front 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 had surface such as a concrete floor; use a new one.