P014C
2ZR-FXE ENGINE CONTROL: SFI SYSTEM: P014C,P014D,P015A,P015B: A/F Sensor Slow Response - Rich to Lean Bank 1 Sensor 1
DESCRIPTION
HINT
Refer to DTC P2195 P2195.
*: Calculated by ECM based on the air fuel ratio sensor output.
MONITOR DESCRIPTION
After the engine has been warmed up, the ECM carries out air-fuel ratio feedback control, and maintains the air-fuel ratio at the theoretical level. In addition, after all the preconditions have been met, active air-fuel ratio control is carried out for approximately. 10 seconds and during active air-fuel ratio control, the ECM measures the response of the air-fuel ratio sensor by increasing or decreasing a specific injection quantity based on the theoretical air-fuel ratio learned during normal air-fuel control. The ECM determines whether there is an air-fuel ratio sensor malfunction at the mid-point of active air-fuel ratio control.
If the air-fuel ratio sensor's response ability is reduced, DTC P014C and P014D are output.
If the air-fuel ratio sensor output timing is delayed, DTC P015A and P015B are output.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
TYPICAL MALFUNCTION THRESHOLDS
Air Fuel Ratio Sensor Slow Response (Rich to Lean)
Air Fuel Ratio Sensor Slow Response (Lean to Rich)
Air Fuel Ratio Sensor Delayed Response (Rich to Lean)
Air Fuel Ratio Sensor Delayed Response (Lean to Rich)
MONITOR RESULT
Refer to Checking Monitor Status Mode 6 Data.
CONFIRMATION DRIVING PATTERN
HINT
Performing this confirmation pattern will activate the air fuel ratio sensor response monitor.
1. Connect the Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the Techstream on.
4. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
5. Turn the power switch off and wait for 30 seconds.
6. Turn the power switch on (IG) and turn the Techstream on.
7. Put the engine in inspection mode Component Tests and General Diagnostics.
8. Enter the following menus: Powertrain / Engine and ECT / Monitor / Current Monitor / O2 Sensor / Details.
9. Check that the RES RATE B1S1 are Incomplete.
10. Start the engine and warm it up (until the engine coolant temperature is 75°C (167°F) or higher) [A].
11. Drive the vehicle at a constant speed of between 47 and 62 mph (75 and 100 km/h) for 10 minutes [B].
12. Check the monitor result values on Techstream by entering the following menus: Powertrain / Engine and ECT / Monitor / Current Monitor / O2 Sensor / Details / RES RATE B1S1.
13. If the values indicated on the Techstream do not change, perform Readiness Monitor Drive Pattern for the air fuel ratio sensor and heated oxygen sensor Monitors, Trips, Drive Cycles and Readiness Codes.
14. Note the value of the Monitor Result.
15. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
16. Read the pending DTCs [C].
HINT
* If a pending DTC is output, the system is malfunctioning.
* If a pending DTC is not output, perform the following procedure.
17. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
18. Input the DTC: P014C, P014D, P015A, P015B.
19. Check the DTC judgment result.
HINT
* If the judgment result shows NORMAL, the system is normal.
* If the judgment result shows ABNORMAL, the system has a malfunction.
20. If the test result is INCOMPLETE or UNKNOWN and no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.
HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
Refer to DTC P2195 P2195.
INSPECTION PROCEDURE
HINT
Malfunctioning areas can be identified by performing the Control the Injection Volume for A/F Sensor function provided in the Active Test. The Control the Injection Volume for A/F Sensor function can help to determine whether the air fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.
The following instructions describe how to conduct the Control the Injection Volume for A/F Sensor operation using the Techstream.
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Put the engine in inspection mode Component Tests and General Diagnostics.
(e) Start the engine.
(f) Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
(g) Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
(h) Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).
(i) Monitor the output voltages of the air fuel ratio and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2) displayed on the Techstream.
HINT
* The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 25%.
* Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
* If there is almost no response from the air fuel ratio sensor, a malfunction of the air fuel ratio sensor is suspected.
NOTICE:
The air fuel ratio sensor has an output delay of a few seconds and the heated oxygen sensor has a maximum output delay of approximately 20 seconds.
- Following the Control the Injection Volume for A/F Sensor procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio and heated oxygen sensors.
- To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / A/F Control System / AFS Voltage B1S1 and O2S B1S2, and then press the graph button on the Data List view.
HINT
* A low air fuel ratio sensor voltage could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich.
* A high air fuel ratio sensor voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean.
* Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.
* Sensor 1 refers to the sensor closest to the engine assembly.
* Sensor 2 refers to the sensor farthest away from the engine assembly.
PROCEDURE
1. CHECK ANY OTHER DTCS OUTPUT (DTC P014C, P014D, P015A OR P015B)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(e) Read the DTCs.
Result:
HINT
If any DTCs other than P014C, P014D, P015A or P015B are output, troubleshoot those DTCs first.
B -- GO TO DTC CHART SFI System
A -- Continue to next step.
2. INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE) P0031
NG -- REPLACE AIR FUEL RATIO SENSOR Removal
OK -- Continue to next step.
3. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM) P2237
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR (AIR FUEL RATIO SENSOR - ECM)
OK -- Continue to next step.
4. INSPECT AIR FUEL RATIO SENSOR
(a) Check that the proper air fuel ratio sensors are installed to the vehicle.
NG -- REPLACE AIR FUEL RATIO SENSOR Removal
OK -- Continue to next step.
5. PERFORM CONFIRMATION DRIVING PATTERN
(a) Drive the vehicle according to the Confirmation Driving Pattern.
NEXT -- Continue to next step.
6. CHECK WHETHER DTC OUTPUT RECURS (DTC P014C, P014D, P015A OR P015B)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
(e) Read the pending DTCs.
Result:
B -- CHECK FOR INTERMITTENT PROBLEMS Check for Intermittent Problems
A -- Continue to next step.
7. REPLACE AIR FUEL RATIO SENSOR
(a) Replace the air fuel ratio sensor Removal.
NEXT -- Continue to next step.
8. PERFORM CONFIRMATION DRIVING PATTERN
(a) Drive the vehicle according to the Confirmation Driving Pattern.
NEXT -- Continue to next step.
9. CHECK WHETHER DTC OUTPUT RECURS (DTC P014C, P014D, P015A OR P015B)
(a) Connect the Techstream to the DLC3.
(b) Turn the power switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.
(e) Read the pending DTCs.
Result:
B -- CHECK ENGINE TO DETERMINE CAUSE OF EXTREMELY RICH OR LEAN ACTUAL AIR FUEL RATIO P0171
A -- END