P0155

SYSTEM DESCRIPTION
The PCM performs ON/OFF control of the heated oxygen sensor 1 heater (front) corresponding to the engine operating condition.

Operation:

CONSULT-II Reference Value in Data Monitor Mode
Specification data are reference values.

On Board Diagnosis Logic:

DTC Confirmation Procedure

NOTE: If "DTC Confirmation Procedure" has been previously conducted, always turn ignition switch "OFF" and wait at least 10 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-II




1. Turn ignition switch "ON" and select "DATA MONITOR" mode with CONSULT-II.
2. Start engine and run it for at least 6 seconds at idle speed.
3. If 1st trip DTC is detected, go to "Diagnostic Procedure" below.

With GST
1. Start engine and run it for at least 6 seconds at idle speed.
2. Turn ignition switch "OFF" and wait at least 10 seconds.
3. Start engine and run it for at least 6 seconds at idle speed.
4. Select "MODE 3" with GST.
5. If DTC is detected, go to "Diagnostic Procedure" below.
- When using GST, "DTC Confirmation Procedure" should be performed twice as much as when using CONSULT-II because GST cannot display MODE 7 (1st trip DTC) concerning this diagnosis. Therefore, using CONSULT-II is recommended.

WIRING DIAGRAM

EC-O2H1B2-01:

EC-O2H1B2-01 -Connector View:

BANK 2




PCM TERMINALS AND REFERENCE VALUE MEASURED BETWEEN EACH TERMINAL AND GROUND.

CAUTION: DO NOT USE PCM GROUND TERMINALS WHEN MEASURING INPUT/OUTPUT VOLTAGE. DOING SO MAY RESULT IN DAMAGE TO THE PCM'S TRANSISTOR. USE A GROUND OTHER THAN PCM TERMINALS, SUCH AS THE GROUND.

Diagnostic Procedure Step 1:

Diagnostic Procedure Step 2:

Diagnostic Procedure Step 3:

Diagnostic Procedure Step 4:

Diagnostic Procedure Step 5:

DIAGNOSTIC PROCEDURE

COMPONENT INSPECTION




HEATED OXYGEN SENSOR 1 HEATER (FRONT)
Check resistance between terminals 3 and 1.
Resistance: 2.3 - 4.3 Ohm at 25 °C (77 °F)
Check continuity between terminals 2 and 1, 3 and 2.
Continuity should not exist.
If NG, replace the heated oxygen sensor 1 (front).

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.
- Before installing new heated oxygen sensor, clean exhaust system threads using Heated Oxygen Sensor Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.