P1130

DTC P1130 A/F SENSOR CIRCUIT RANGE/PERFORMANCE 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:
- P1130 means malfunction of bank 1 A/F sensor circuit.
- P1150 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.
- After confirming DTC P1130, use the OBD II scan tool or hand-held tester to confirm voltage output of A/F sensor (AFS B1 S1/O2S B1 S1) from the CURRENT DATA.
- The A/F sensor's output voltage and the short-term fuel trim value can be read using the OBD II scan tool or hand-held tester.
- The ECM controls the voltage of the AF1A+, AF2A+, AF1A- and AF2A- terminals of the ECM to the fixed voltage. Therefore, it is impossible to confirm the A/F sensor output voltage without the OBD II scan tool or hand-held tester.
- The OBD II scan tool (excluding hand-held tester) displays the 1/5 of the A/F sensor output voltage which is displayed on the hand-held tester.

Wiring Diagram:

Step 1:

Step 2:

INSPECTION PROCEDURE

HINT:
- If DTC P1130 is displayed, check the bank 1 sensor 1 circuit.
- If DTC P1150 is displayed, check the bank 2 sensor 1 circuit.
- 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.