Brand:

Toyota

Model Name:

Yaris NCP90 91 92 93

Manual:

Repair Manual

Section:

1Nz-Fe Engine Control System

Title:

Sfi System

  1. Description

  2. Wiring diagram

  3. Confirmation driving pattern

  4. Inspection procedure

  5. Check any other dtcs output (in addition to dtc p0130, p2195 and/or p2196)

  6. Read value using intelligent tester (output voltage of heated oxygen sensor (sensor 1))

  7. Inspect heated oxygen sensor (heater resistance)

  8. Inspect integration no.1 relay (efi relay)

  9. Check harness and connector (heated oxygen sensor (sensor 1) - ecm)

  10. Check air induction system

  11. Check fuel pressure

  12. Inspect fuel injector

  13. Perform confirmation driving pattern

  14. Check whether dtc output recurs (dtc p0130, p2195 and/or p2196)

DTC P0130 Oxygen Sensor Circuit Malfunction (Bank 1 Sensor 1)

DTC P2195 Oxygen Sensor Signal Stuck Lean (Bank 1 Sensor 1)

DTC P2196 Oxygen Sensor Signal Stuck Rich (Bank 1 Sensor 1)

HINT:
Sensor 1 refers to the sensor mounted in front of the Three-Way Catalytic Converter (TWC) and located near the engine assembly.

DESCRIPTION

In order to obtain a high purification rate of the carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) components in the exhaust gas, a TWC is used. For the most efficient use of the TWC, the air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric air-fuel level. For the purpose of helping the ECM to deliver accurate air-fuel ratio control, a Heated Oxygen (HO2) sensor is used. The HO2 sensor is located in front of the TWC, and detects the oxygen concentration in the exhaust gas.
Since the sensor is integrated with the heater that heats the sensing portion, it is possible to detect the oxygen concentration even when the intake air volume is low (the exhaust gas temperature is low). When the air-fuel ratio becomes lean, the oxygen concentration in the exhaust gas is rich. The HO2 sensor indicates to the ECM that the pre-TWC air-fuel ratio is lean (low voltage, i.e. less than 0.45 V).
Conversely, when the air-fuel ratio is richer than the stoichiometric air-fuel level, the oxygen concentration in the exhaust gas becomes lean. The HO2 sensor indicates to the ECM that the pre-TWC air-fuel ratio is rich (high voltage, i.e. more than 0.45 V). The HO2 sensor has the property of changing its output voltage drastically when the air-fuel ratio is close to the stoichiometric level. The ECM uses the supplementary information from the HO2 sensor to determine whether the air-fuel ratio in front of the TWC is rich or lean, and adjusts the fuel injection time accordingly. Thus, if the HO2 sensor is working improperly due to internal malfunctions, the ECM is unable to compensate for deviations in the primary air-fuel ratio control.

Open or short in HO2 sensor (sensor 1) circuit Yaris

HINT:
The ECM provides a pulse width modulated control circuit to adjust the current through the heater. The heated oxygen sensor heater circuit uses a relay on the +B side of the circuit.

Open or short in HO2 sensor (sensor 1) circuit Yaris


DTC No.
DTC Detection Conditions
Trouble Areas
P0130
Voltage output of Heated Oxygen (HO2) sensor remains at 0.4 V or more, and 0.5 V or less, during idling with warm engine (2 trip detection logic)
  1. Open or short in HO2 sensor (sensor 1) circuit
  2. HO2 sensor (sensor 1)
  3. Integration relay (EFI relay)
  4. Air induction system
  5. Fuel pressure
  6. Injector
  7. ECM
P2195
Output voltage of HO2 sensor remains at 0.5 V or less during idling with warm engine (2 trip detection logic)
P2196
Output voltage of HO2 sensor remains at 0.4 V or more during idling with warm engine (2 trip detection logic)

WIRING DIAGRAM


(a) Connect an intelligent tester to the DLC3. Yaris


CONFIRMATION DRIVING PATTERN


(a) Connect an intelligent tester to the DLC3. Yaris

HINT:
This confirmation driving pattern is used in the "PERFORM CONFIRMATION DRIVING PATTERN" procedure of the following diagnostic troubleshooting procedure.
  1. (a) Connect an intelligent tester to the DLC3.
  2. (b) Turn the ignition switch to ON and turn the tester on.
  3. (c) Clear DTCs (Click here).
  4. (d) Switch the ECM from normal mode to check mode (Click here).
  5. (e) Start the engine.
  6. (f) Allow the engine to idle for 120 seconds or more until the engine coolant temperature reaches 75°C (167°F).
  7. (g) Drive the vehicle at a vehicle speed of more than 40 km/h (25 mph) for 20 seconds or more.
  8. (h) Allow the engine to idle for 30 seconds or more.
  9. (i) Repeat steps (g) and (h) described above at least 3 times.
  10. (j) Allow the engine to idle for 40 seconds or more.
HINT:
The MIL is illuminated during step (f) if a malfunction still exists.
NOTICE:
If the conditions in this test are not strictly followed, malfunctions may not be detected.

INSPECTION PROCEDURE

HINT:
It is possible that the malfunctioning area can be found using the Active Test Control operation. The Active Test can determine if the heated oxygen sensor or other potential trouble areas are malfunctioning or not.
The injection volume can be switched to -12.5% (decrease) or +25% (increase) by the Active Test.
The Active Test procedure enables a technician to check and graph the voltage outputs of the heated oxygen sensors.
  1. Procedure:
    1. Connect an intelligent tester to the DLC3.
    2. Turn the ignition switch to ON.
    3. Warm up the engine by running the engine at 2,500 rpm for approximately 90 seconds.
    4. Select the following menu items: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
    5. Perform the Active Test while the engine is idling.
Standard:
The heated oxygen sensor reacts in accordance with the increases and decreases in injection volume:
+25% → RICH output: More than 0.5 V
-12.5% → LEAN output: Less than 0.4 V
NOTICE:
The heated oxygen sensor (sensor 1) has an output delay of a few seconds and the heated oxygen sensor (sensor 2) has a maximum output delay of 20 seconds.
If the vehicle is short of fuel, the air-fuel ratio becomes LEAN and the DTCs are recorded.

Case
Heated Oxygen Sensor (Sensor 1) Output Voltage
Heated Oxygen Sensor (Sensor 2) Output Voltage
Main Suspected Trouble Area
1
Heated oxygen sensor (Sensor 1) Yaris
Heated oxygen sensor (Sensor 1) Yaris
Heated oxygen sensor (Sensor 1) Yaris
Heated oxygen sensor (Sensor 1) Yaris
-
2
Heated oxygen sensor (Sensor 1) Yaris
Heated oxygen sensor (Sensor 1) Yaris
Heated oxygen sensor (Sensor 1) Yaris
Heated oxygen sensor (Sensor 1) Yaris
  1. Heated oxygen sensor (Sensor 1)
  2. Heated oxygen sensor heater (Sensor 1)
  3. Heated oxygen sensor circuit (Sensor 1)
3
Heated oxygen sensor (Sensor 2) Yaris
Heated oxygen sensor (Sensor 2) Yaris
Heated oxygen sensor (Sensor 2) Yaris
Heated oxygen sensor (Sensor 2) Yaris
  1. Heated oxygen sensor (Sensor 2)
  2. Heated oxygen sensor heater (Sensor 2)
  3. Heated oxygen sensor circuit (Sensor 2)
4
Injector Yaris
Injector Yaris
Injector Yaris
Injector Yaris
  1. Injector
  2. Fuel pressure
  3. Gas leak from exhaust system (Air-fuel ratio extremely RICH or LEAN)
HINT:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, if the engine was warmed up or not, if the air-fuel ratio was LEAN or RICH, and other data from the time the malfunction occurred.
1.CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0130, P2195 AND/OR P2196)

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Select the following menu items: Powertrain / Engine and ECT / DTC.

  1. Read DTCs.

    Result:
    Display (DTC Output)
    		Proceed To
    P0130, P2195 and/or P2196
    		A
    P0130, P2195 and/or P2196 and other DTCs
    		B
    HINT:
    If any DTCs other than P0130, P2195 and/or P2196 are output, troubleshoot those DTCs first.


Bnext
GO TO DTC CHART (Click here)
A
next down

2.READ VALUE USING INTELLIGENT TESTER (OUTPUT VOLTAGE OF HEATED OXYGEN SENSOR (SENSOR 1))

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Select the following menu items: Powertrain / Engine and ECT / Data List / O2S B1 S1.

  1. Allow the engine to run for 90 seconds at 2,500 rpm.

  1. Read the Heated Oxygen (HO2) sensor voltage while the engine is idling.

    OK:
    HO2 sensor voltage alternates between below 0.4 V and more than 0.5 V (see the following table).

    Disconnect the C36 HO2 sensor (sensor 1) connector. Yaris



OKnext
Go to step 9
NG
next down

3.INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)
Disconnect the C36 HO2 sensor (sensor 1) connector. Yaris

  1. Disconnect the C36 HO2 sensor (sensor 1) connector.

  1. Check the resistance.

    Standard resistance:
    Tester Connections
    		Specified Conditions
    HT1A (1) - +B (2)
    		5.3 to 7.5 Ω at 20 °C (68°F)
    HT1A (1) - E2 (4)
    		10 kΩ or higher

  1. Reconnect the HO2 sensor connector.



NGnext
REPLACE HEATED OXYGEN SENSOR (Click here)
OK
next down

4.INSPECT INTEGRATION NO.1 RELAY (EFI RELAY)
Remove the integration relay from the engine room relay block. Yaris

  1. Remove the integration relay from the engine room relay block.

  1. Inspect the EFI fuse.

    1. Remove the EFI fuse from the integration relay.

    2. Check the EFI fuse resistance.

      Standard resistance:
      Below 1 Ω

    3. Reinstall the EFI fuse.

  1. Inspect the EFI relay.

    1. Check the EFI relay resistance.

      Standard resistance:
      Tester Connections
      		Specified Conditions
      1C-1 - 1A-4
      		10 kΩ or higher
      Below 1 Ω
      (Apply battery voltage between terminals 1A-2 and 1A-3)

  1. Reinstall the integration relay.



NGnext
REPLACE INTEGRATION NO.1 RELAY
OK
next down

5.CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR (SENSOR 1) - ECM)
Disconnect the C36 HO2 sensor (sensor 1) connector. Yaris

Disconnect the C36 HO2 sensor (sensor 1) connector. Yaris

  1. Disconnect the C36 HO2 sensor (sensor 1) connector.

  1. Disconnect the C20 ECM connector.

  1. Check the resistance.

    Standard resistance (Check for open):
    Tester Connections
    		Specified Conditions
    OX1A (C36-3) - OX1A (C20-112)
    		Below 1 Ω
    HT1A (C36-1) - HT1A (C20-109)
    Standard resistance (Check for short):
    Tester Connections
    		Specified Conditions
    OX1A (C36-3) or OX1A (C20-112) - Body ground
    		10 kΩ or higher
    HT1A (C36-1) or HT1A (C20-109) - Body ground

  1. Reconnect the HO2 sensor connector.

  1. Reconnect the ECM connector.



NGnext
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
next down

6.CHECK AIR INDUCTION SYSTEM

  1. Check the air induction system for vacuum leaks.

    OK:
    No leakage from air induction system.


NGnext
REPAIR OR REPLACE AIR INDUCTION SYSTEM
OK
next down

7.CHECK FUEL PRESSURE

  1. Check the fuel pressure (Click here).



NGnext
REPAIR OR REPLACE FUEL SYSTEM
OK
next down

8.INSPECT FUEL INJECTOR

  1. Check the injector injection (whether fuel volume is high or low, and whether injection pattern is poor).



NGnext
REPLACE FUEL INJECTOR
OK
next down
REPLACE HEATED OXYGEN SENSOR (Click here)

9.PERFORM CONFIRMATION DRIVING PATTERN
HINT:
Clear all DTCs before performing the confirmation driving pattern.

NEXT
next down

10.CHECK WHETHER DTC OUTPUT RECURS (DTC P0130, P2195 AND/OR P2196)

  1. Connect an intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Select the following menu items: Powertrain / Engine and ECT / DTC.

  1. Read DTCs.

Result:
Display (DTC Output)
Proceed To
P0130, P2195 and/or P2196
A
No output
B


Bnext
CHECK FOR INTERMITTENT PROBLEMS (Click here)
A
next down
REPLACE HEATED OXYGEN SENSOR (Click here)