P0133

P0133 A/F Sensor 1

Component Description

The A/F sensor 1 is a planar dual-cell limit current sensor. The sensor element of the A/F sensor 1 is the combination of a Nernst concentration cell (sensor cell) with an oxygen-pump cell, which transports ions. It has a heater in the element.





The sensor is capable of precise measurement = 1, but also in the lean and rich range. Together with its control electronics, the sensor outputs a clear, continuous signal throughout a wide range (0.7 << air).


The exhaust gas components diffuse through the diffusion gap at the electrode of the oxygen pump and Nernst concentration cell, where they are brought to thermodynamic balance.

An electronic circuit controls the pump current through the oxygen-pump cell so that the composition of the exhaust gas in the diffusion gap remains constant at = 1. Therefore, the A/F sensor 1 is able to indicate air-fuel ratio by this pumping of current. In addition, a heater is integrated in the sensor to ensure the required operating temperature of 700 - 800 °C (1,292 - 1,472 °F).





On Board Diagnosis Logic

To judge the malfunction of air fuel ratio (A/F) sensor 1, this diagnosis measures response time of the A/F signal computed by ECM from the air fuel ratio (A/F) sensor 1 signal. The time is compensated by engine operating (speed and load), fuel feedback control constant, and the air fuel ratio (A/F) sensor 1 temperature index. Judgment is based on whether the compensated time (the A/F sensor 1 signal cycling time index) is inordinately long or not.






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 more than 11 V at idle.

with SDT

1) Start engine and warm it up to normal operating temperature.
2) Turn ignition switch OFF and wait at least 10 seconds.
3) Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1minute under no load.
4) Let engine idle for 1 minute.
5) Select "A/F SEN1(B1) P1278/P1279" of "A/F SEN1" in "DTC work support" mode with SDT.
6) Touch "START".

If "COMPLETED" appears on SDT screen, go to step 10.

If "COMPLETED" does not appear on SDT screen, go to the following steps.
7) After perform the following procedure, "TESTING" will be displayed on the SDT screen.
a) Increase the engine speed up to between 4,000 and 5,000 rpm and maintain that speed for 10 seconds.
b) Fully release accelerator pedal and then let engine idle for about 10 seconds.
If "TESTING" is not displayed after 10 seconds, refer to [Power Supply and Ground Circuit Check] SDT Reference Value in Data List Mode.
8) Wait for about 20 seconds at idle under the condition that "TESTING" is displayed on the SDT screen.
9) Make sure that "TESTING" changes to "COMPLETED".

If "TESTING" changed to "OUT OF CONDITION", refer to SDT Reference Value in Data List Mode.
10) Make sure that "OK" is displayed after touching "DTC check".

If "NG" is displayed, go to "Diagnosis Procedure".

with GST

1) Start engine and warm it up to normal operating temperature.
2) Select Service $01 with GST.
3) Calculate the total value of "Short term fuel trim" and "Long term fuel trim" indications.

Make sure that the total percentage should be within ±15%.

If OK, go to the following steps.

If NG, check the following.
- Intake air leaks
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Fuel injector
- Incorrect PCV hose connection
- PCV valve
- Mass air flow sensor
4) Turn ignition switch OFF and wait at least 10 seconds.
5) Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1minute under no load.
6) Let engine idle for 1 minute.
7) Increase the engine speed up to between 4,000 and 5,000 rpm and maintain that speed for 10 seconds.
8) Fully release accelerator pedal and then let engine idle for about 1 minute.
9) Select Service $07 with GST.

If the 1st trip DTC is displayed, go to "Diagnosis Procedure".

Diagnosis Procedure

1. CHECK GROUND CONNECTIONS

1 Turn ignition switch OFF.
2 Loosen and retighten two ground screws on the body. Refer to Power Supply and Ground Circuit Check.






OK or NG
OK
GO TO 2.
NG
Repair or replace ground connections.

2. RETIGHTEN AIR FUEL RATIO (A/F) SENSOR 1

Loosen and retighten the air fuel ratio (A/F) sensor 1. Refer to [Exhaust Manifold and Three Way Catalyst: Removal and Installation [QR25DE] Exhaust Manifold and Three Way Catalyst Removal and Installation ].







GO TO 3.

3. CHECK EXHAUST GAS LEAK

1 Start engine and run it at idle.
2 Listen for an exhaust gas leak before three way catalyst (manifold).






OK or NG
OK
GO TO 4.
NG
Repair or replace.

4. CHECK FOR INTAKE AIR LEAK

Listen for an intake air leak after the mass air flow sensor.

OK or NG
OK
GO TO 5.
NG
Repair or replace.

5. CLEAR THE SELF-LEARNING DATA

With SDT
1 Start engine and warm it up to normal operating temperature.
2 Select "SELF-LEARNING CONT" in "Utility" mode with SDT.
3 Clear the self-learning control coefficient by touching "CLEAR" or "START".
4 Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0172 detected?
Is it difficult to start engine?
Without SDT
1 Start engine and warm it up to normal operating temperature.
2 Turn ignition switch OFF.
3 Disconnect mass air flow sensor harness connector.





4 Restart engine and let it idle for at least 5 seconds.
5 Stop engine and reconnect mass air flow sensor harness connector.
6 Make sure DTC P0102 is displayed.
7 Erase the DTC memory. Refer to [On Board Diagnosis Function] On Board Diagnosis Function (Without SDT) or [SDT Function] SDT Function (With SDT).
8 Make sure DTC P0000 is displayed.
9 Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171 or P0172 detected?
Is it difficult to start engine?

Yes or No
Yes
Perform trouble diagnosis for DTC P0171 or P0172. Refer to [P0031, P0032 A/F Sensor 1 Heater] P0171 or P0172.
No
GO TO 6.

6. CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1 Turn ignition switch OFF.
2 Disconnect A/F sensor 1 harness connector.





3 Turn ignition switch ON.
4 Check voltage between A/F sensor 1 terminal 3 and ground with SDT or tester.











OK or NG
OK
GO TO 8.
NG
GO TO 7.

7. DETECT MALFUNCTIONING PART

Check the following.
- Harness connectors E2, F32
- IPDM E/R harness connector E119
- 15 A fuse (No.54)
- Harness for open or short between A/F sensor 1 and fuse


Repair or replace harness or connectors.

8. CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1 Turn ignition switch OFF.
2 Disconnect ECM harness connector.
3 Check harness continuity between the following terminals. Refer to Wiring Diagram.










4 Check harness continuity between ECM terminals 16, 35, 56, 75 or A/F sensor 1 terminals 1, 2, 5, 6 and ground. Refer to Wiring Diagram.






5 Also check harness for short to power.

OK or NG
OK
GO TO 9.
NG
Repair open circuit, short to ground or short to power in harness or connectors.

9. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HEATER

Refer to P0031.

OK or NG
OK
GO TO 10.
NG
GO TO 13.

10. CHECK MASS AIR FLOW SENSOR

Refer to [P0101 MAF Sensor] P0101.

OK or NG
OK
GO TO 11.
NG
Replace mass air flow sensor. Refer to [Air Cleaner and Air Duct: Exploded View] Exploded View.

11. CHECK PCV VALVE

Refer to [Positive Crankcase Ventilation Circuit Check] Testing and Inspection.

OK or NG
OK
GO TO 12.
NG
Repair or replace PCV valve. Refer to [Rocker Cover: Exploded View] Exploded View.

12. CHECK INTERMITTENT INCIDENT

Perform [Service Information for Electrical Incident: Intermittent Incident] Service Information for Electrical Incident: Intermittent Incident.

OK or NG
OK
GO TO 13.
NG
Repair or replace.

13. REPLACE AIR FUEL RATIO (A/F) SENSOR 1

Replace air fuel ratio (A/F) sensor 1. Refer to [Exhaust Manifold and Three Way Catalyst: Exploded View [QR25DE] Exhaust Manifold and Three Way Catalyst Exploded View ].

CAUTION:
- Discard any air fuel ratio (A/F) 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 air fuel ratio (A/F) sensor, clean exhaust system threads using Heated Oxygen Sensor Thread Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant (commercial service tool).


INSPECTION END