P1133
DTC P1133 A/F SENSOR CIRCUIT RESPONSE MALFUNCTION (BANK 1 SENSOR 1)CIRCUIT DESCRIPTION
DTC Detecting Condition:
To obtain a high purification rate of the CO, HC and NOx components of the exhaust gas, a three-way catalytic converter is used. For the most efficient use of the three-way catalytic converter, the air-fuel ratio must be precisely controlled so that it is always close to the stoichiometric air-fuel ratio.
The A/F sensor has the characteristic that it provides output voltage* being approximately proportional to the existing air-fuel ratio. The A/F sensor output voltage* is used to provide feedback for the ECM to control the air-fuel ratio.
By the A/F sensor output, the ECM can determine the deviation amount from the stoichiometric air-fuel ratio and control the proper injection time immediately. If the A/F sensor is out of order, ECM is unable to perform the accurate air-fuel ratio control.
The A/F sensor is equipped with a heater which heats the zirconia element. The heater is controlled by the ECM. When the intake air volume is low (the temperature of the exhaust gas is low), the current flows to the heater to heat the sensor for the accurate oxygen concentration detection.
*: The voltage value changes at the inside of the ECM only.
HINT:
- P1133 means malfunction of bank 1 A/F sensor circuit.
- P1153 means malfunction of bank 2 A/F sensor circuit.
- Bank 1 refers to the bank that includes cylinder No. 1.
- Bank 2 refers to the bank that includes cylinder No.2.
- Sensor 1 refers to the sensor closest to the engine body.
CONFIRMATION DRIVING PATTERN
1. Connect the hand-held tester to the DLC3. (*1)
2. Switch the hand-held tester from the normal mode to the check mode. (*1)
3. Start the engine and warm it up with all the accessory switches OFF. (*2)
4. Drive the vehicle at 60 - 120 km/h (38 - 75 mph) and engine speed at 1,400 - 3,200 rpm for 3 - 5 min. (*3)
HINT: If a malfunction exists, the MIL will light up during step (*3).
NOTE: If the conditions in this test are not strictly followed, detection of the malfunction will not be possible.
If you do not have a hand-held tester, turn the ignition switch OFF after performing steps (*2) and (*3), then perform steps (*2) and (*3) again.
Wiring Diagram:
Step 1 - 2:
Step 2 (continued):
Step 3 - 4:
Step 5:
Step 6 - 10:
Step 11 - 18:
INSPECTION PROCEDURE
HINT:
- This diagnostics procedure is designed to work for both P1133 and P1153.
- The A/F sensor signal must be checked using the hand-held tester or OBD II scan tool.
- DTC P1133 or P1153 may be also detected, when the air fuel ratio is stuck rich or lean.
- Read freeze frame data using the hand-held tester or the OBD II scan tool, as freeze frame data records the engine conditions when the malfunction is detected. When troubleshooting, this is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich. etc. at the time of the malfunction.
CHECK FOR INTERMITTENT PROBLEMS
Hand-held tester only:
By putting the vehicle's ECM in the check mode, the 1 trip detection logic is possible instead of the 2 trip detection logic and the sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.
1. Clear the DTCs.
2. Set the check mode.
3. Perform a simulation test.
4. Check the connector and terminal.
5. Handle the connector.