| DTC Code | DTC Name |
|---|---|
| P2A00 | A/F Sensor Circuit Slow Response (Bank 1 Sensor 1) |
| P2A03 | A/F Sensor Circuit Slow Response (Bank 2 Sensor 1) |
DESCRIPTION
Refer to DTC P2195 Click here.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| P2A00 | The calculated value of the Air Fuel ratio (A/F) sensor response rate deterioration level is less than the threshold (2 trip detection logic). |
|
| P2A03 | The calculated value of the Air Fuel ratio (A/F) sensor response rate deterioration level is less than the threshold (2 trip detection logic). |
|
MONITOR DESCRIPTION
After the engine is warmed up, the ECM performs air-fuel ratio feedback control to maintain the air-fuel ratio at the stoichiometric level. In addition, active A/F control is performed for approximately 10 seconds after the preconditions are met in order to measure the A/F sensor response rate. During active A/F control, the ECM forcibly increases and decreases the injection volume a certain amount, based on the stoichiometric air-fuel ratio learned during normal air-fuel ratio control, and measures the A/F sensor response rate. The ECM receives a signal from the A/F sensor while performing active A/F control and uses it to calculate the A/F sensor response rate deterioration level.
If the A/F sensor response rate deterioration level is less than the threshold, the ECM interprets this as a malfunction and stores DTC(s).
CONFIRMATION DRIVING PATTERN
Tech Tips
Performing this confirmation pattern will activate the air fuel ratio sensor response monitor.
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG).
Turn the tester on.
Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
Turn the engine switch off and wait for at least 30 seconds.
Start the engine and warn it up (until the engine coolant temperature 75°C (167°F)). [A]
Turn the tester on.
Drive the vehicle at a constant speed of between 60 km/h and 120 km/h (37 mph and 75 mph) for 10 minutes. [B]
CAUTION:
When performing the confirmation driving pattern, obey all speed limits and traffic laws.
Enter the following menus: Powertrain / Engine and ECT / DTC / Pending.
Read the pending DTC.
If a pending DTC is output, the system is malfunctioning.
Tech Tips
If a pending DTC is not output, perform the following procedure.
Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
Input the DTC P2A00 or P2A03.
Check the DTC judgment result.
| Tester Display | Description |
|---|---|
| NORMAL |
|
| ABNORMAL |
|
| INCOMPLETE |
|
| UNKNOWN |
|
Tech Tips
If the judgment result shows ABNORMAL, the system has a malfunction.
If the judgment result shows INCOMPLETE or UNKNOWN, perform step [B] and check the DTC judgment result again.
WIRING DIAGRAM
Refer to DTC P2195 Click here.
CAUTION / NOTICE / HINT
Tech Tips
DTC P2A00 and P2A03 are for Euro-OBD only.
Sensor 1 refers to the sensor mounted in front of the Three-Way Catalytic Converter (TWC) and located near the engine assembly.
DTC P2A00 indicates malfunctions related to the bank 1 A/F sensor.
DTC P2A03 indicates malfunctions related to the bank 2 A/F sensor.
Bank 1 refers to the bank that includes the No. 1 cylinder.
Bank 2 refers to the bank that includes the No. 2 cylinder.
DTC P2A00 or P2A03 may be stored when the air-fuel ratio is stuck rich or lean.
A low A/F sensor voltage could be caused by a rich air-fuel mixture. Check for conditions that would cause the engine to run rich.
A high A/F 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 intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, 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.
PROCEDURE
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2A00 AND/OR P2A03)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG).
Turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC.
Read DTCs.
| Result | Proceed to |
|---|---|
| P2A00 and/or P2A03 are output | A |
| P2A00 and/or P2A03 and other DTCs are output | B |
Tech Tips
If any DTCs relating to the A/F sensor (DTCs for the A/F sensor heater or A/F sensor admittance) are output, troubleshoot those DTCs first.
| B |
|
GO TO DTC CHART Click here |
| A |
|
INSPECT AIR FUEL RATIO SENSOR (HEATER RESISTANCE)
Disconnect the Air Fuel ratio (A/F) sensor connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
| NG |
|
REPLACE AIR FUEL RATIO SENSOR Click here |
| OK |
|
CHECK HARNESS AND CONNECTOR (ECM - AIR FUEL RATIO SENSOR)
Disconnect the Air Fuel ratio (A/F) sensor connector.
Measure the voltage according to the value(s) in the table below.
| Standard Voltage | |||||||||
|---|---|---|---|---|---|---|---|---|---|
|
Turn the engine switch off.
Disconnect the ECM connector.
Measure the resistance according to the value(s) in the table below.
| Standard Resistance | |||||||||||||||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
|||||||||||||||||||||||||||||||||||||||
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR |
| OK |
|
PERFORM CONFIRMATION DRIVING PATTERN
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P2A00 AND/OR P2A03)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC / Pending.
Read pending DTCs.
| Result | Proceed to |
|---|---|
| P2A00 and/or P2A03 is output | A |
| No DTC is output | B |
| B |
|
CHECK FOR INTERMITTENT PROBLEMS Click here |
| A |
|
REPLACE AIR FUEL RATIO SENSOR
Replace the air fuel ratio sensor Click here.
| NEXT |
|
PERFORM CONFIRMATION DRIVING PATTERN
| NEXT |
|
CHECK WHETHER DTC OUTPUT RECURS (DTC P2A00 AND/OR P2A03)
Connect the intelligent tester to the DLC3.
Turn the engine switch on (IG) and turn the tester on.
Enter the following menus: Powertrain / Engine and ECT / DTC / Pending.
Read pending DTCs.
| Result | Proceed to |
|---|---|
| No DTC is output | A |
| P2A00 and/or P2A03 are output | B |
| A |
|
END |
| B |
|
REPLACE ECM Click here |