P0134

COMPONENT DESCRIPTION
The heated oxygen sensor 1 (front) is placed into the exhaust manifold. It detects the amount of oxygen in the exhaust gas compared to the outside air. The heated oxygen sensor 1 (front) has a closed-end tube made of ceramic zirconia. The zirconia generates voltage from approximately 1 V in richer conditions to 0 V in leaner conditions. The heated oxygen sensor 1 (front) signal is sent to the PCM. The PCM adjusts the injection pulse duration to achieve the ideal air-fuel ratio. The ideal air-fuel ratio occurs near the radical change from 1 V to 0 V.

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

ON BOARD DIAGNOSIS LOGIC
To judge the malfunction, the diagnosis checks that the heated oxygen sensor 1 (front) output is not inordinately high.

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.

With CONSULT-II
1. Start engine and warm it up to normal operating temperature.

2. Turn ignition switch "OFF" and wait at least 10 seconds.
3. Turn ignition switch "ON".
4. Select "DATA MONITOR" mode with CONSULT-II.
5. Restart engine and let it idle for 2 minutes.
6. If 1st trip DTC is detected, go to "Diagnostic Procedure" below.

With GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch "OFF" and wait at least 10 seconds.
3. Restart engine and let it idle for 2 minutes.
4. Turn ignition switch "OFF" and wait at least 10 seconds.
5. Restart engine and let it idle for 2 minutes.
6. Select "MODE 3" with GST.
7. 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-O2S1B1-01 -Connector View:

BANK 1

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 (FRONT)

With CONSULT-II
1. Start engine and warm it up to normal operating temperature.

2. Select "MANU TRIG" in "DATA MONITOR" mode, and select "HO2S1 (B1)/(B2)" and "HO2S1 MNTR (B1)/(B2)".
3. Hold engine speed at 2,000 rpm under no load during the following steps.
4. Touch "RECORD" on CONSULT-II screen.

5. Check the following.
- "HO2S1 MNTR (B1)/(B2)" in "DATA MONITOR" mode changes from "RICH" to "LEAN" to "RICH" five times in 10 seconds.
5 times (cycles) are counted as shown below:
R = "HO2S1 MNTR (B1)/(B2)", "RICH"
L = "HO2S1 MNTR (B1)/(B2)", "LEAN"
- "HO2S1 (B1)/(B2)" voltage goes above 0.6 V at least once.
- "HO2S1 (B1)/(B2)" voltage goes below 0.3 V at least once.
- "HO2S1 (B1)/(B2)" voltage never exceeds 1.0 V.

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.

Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.

2. Set voltmeter probes between PCM terminal 62 (HO2S1 bank 1) or 94 (HO2S1 bank 2) and engine ground.
3. Check the following with engine speed held at 2,000 rpm constant under no load.
- The voltage fluctuates between 0 to 0.3 V and 0.6 to 1.0 V more than five times within 10 seconds.
1 time: 0 - 0.3 V -> 0.6 - 1.0 V -> 0 - 0.3 V
2 times: 0 - 0.3 V -> 0.6 - 1.0 V -> 0 - 0.3 V -> 0.6 - 1.0 V -> 0 - 0.3 V
- The maximum voltage is over 0.6 V at least one time.
- The minimum voltage is below 0.3 V at least one time.
- The voltage never exceeds 1.0 V.

CAUTION:
- Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto 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.