DTC    P2237    Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1)

DTC    P2238    Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 1 Sensor 1)

DTC    P2239    Oxygen (A/F) Sensor Pumping Current Circuit High (Bank 1 Sensor 1)

DTC    P2252    Oxygen (A/F) Sensor Reference Ground Circuit Low (Bank 1 Sensor 1)

DTC    P2253    Oxygen (A/F) Sensor Reference Ground Circuit High (Bank 1 Sensor 1)

for Preparation Click here


DESCRIPTION

Refer to DTC P2195 (Click here).

DTC No.
DTC Detection Condition
Trouble Area
P2237
Open in the circuit between terminals A1A+ and A1A- of the air fuel ratio sensor while engine is running (2 trip detection logic).
  1. Open in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. ECM
P2238
  1. Case 1
    Condition (a) or (b) continues for 5.0 seconds or more (2 trip detection logic):
    (a) A1A+ voltage is 0.5 V or less
    (b) A1A+ - A1A- is 0.1 V or less
  2. Case 2
    Air fuel ratio sensor admittance is less than 0.0074 1/Ω (2 trip detection logic):
  1. Open or short in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. ECM
P2239
A1A+ voltage is higher than 4.5 V for 5 seconds (2 trip detection logic).
  1. Open or short in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. ECM
P2252
A1A- voltage is 0.5 V or less for 5 seconds (2 trip detection logic).
  1. Open or short in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. ECM
P2253
A1A- voltage is higher than 4.5 V for 5 seconds (2 trip detection logic).
  1. Open or short in air fuel ratio sensor (sensor 1) circuit
  2. Air fuel ratio sensor (sensor 1)
  3. ECM

MONITOR DESCRIPTION

These DTCs are output when there is an open or short in the air fuel ratio sensor circuit, or if air fuel ratio sensor output drops.
To detect these problems, the voltage of the air fuel ratio sensor is monitored when turning the power switch on (IG), and the admittance (admittance is an electrical term that indicates the ease of flow of current) is checked while driving. If the voltage of the air fuel ratio sensor is between 0.5 V and 4.5 V, it is considered normal. If the voltage is outside of the specified range, or the admittance is below the standard value, the ECM will determine that there is a malfunction in the air fuel ratio sensor. If the same malfunction is detected in the next driving cycle, the MIL is illuminated and a DTC is stored.
The air fuel ratio sensor varies its output voltage in proportion to the air-fuel ratio. If the air fuel ratio sensor impedance (alternating current resistance) or output voltage deviates greatly from the standard range, the ECM determines that there is an open or short in the air fuel ratio sensor circuit.

MONITOR STRATEGY


Required Sensors/Components (Main)
Air fuel ratio sensor
Frequency of Operation
Continuous

CONFIRMATION DRIVING PATTERN

  1. Put the engine in inspection mode (maintenance mode) (Click here).
  2. Start the engine and wait 5 minutes or more.

WIRING DIAGRAM

Refer to DTC P2195 (Click here).

INSPECTION PROCEDURE

HINT:
  1. Refer to "Data List / Active Test" [AFS Voltage B1S1] (Click here).
  2. Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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.
  3. Sensor 1 refers to the sensor closest to the engine assembly.
  4. Sensor 2 refers to the sensor farthest away from the engine assembly.

1.CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM)

  1. Disconnect the air fuel ratio sensor connector.

  1. Disconnect the ECM connector.

  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:

    Tester Connection
    		Condition
    		Specified Condition
    D23-1 (HA1A) - D27-18 (HA1A)
    		Always
    		Below 1 Ω
    D23-3 (A1A+) - D27-103 (A1A+)
    		Always
    		Below 1 Ω
    D23-4 (A1A-) - D27-126 (A1A-)
    		Always
    		Below 1 Ω
    D23-1 (HA1A) or D27-18 (HA1A) - Body ground
    		Always
    		10 kΩ or higher
    D23-3 (A1A+) or D27-103 (A1A+) - Body ground
    		Always
    		10 kΩ or higher
    D23-4 (A1A-) or D27-126 (A1A-) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.REPLACE AIR FUEL RATIO SENSOR

  1. Replace the air fuel ratio sensor (Click here).


NEXT


3.CHECK WHETHER DTC OUTPUT RECURS

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the tester on.

  1. Clear the DTCs.

  1. Drive the vehicle referring to the Confirmation Driving Pattern.

  1. Enter the following menus: Powertrain / Engine and ECT / DTC / Pending.

  1. Read the Pending DTCs.
    Result 
    Result
    		Proceed to
    DTC is not output
    		A
    DTC P2237, P2238, P2239, P2252 or P2253 is output
    		B



B
REPLACE ECM (Click here)
A

END