DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 1GR-FE

DESCRIPTION

MONITOR DESCRIPTION

WIRING DIAGRAM

CONFIRMATION DRIVING PATTERN

INSPECTION PROCEDURE

CHECK HARNESS AND CONNECTOR (A/F SENSOR - ECM)

REPLACE AIR FUEL RATIO SENSOR

PERFORM CONFIRMATION DRIVING PATTERN

CHECK WHETHER DTC OUTPUT RECURS

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 P2240 Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 2 Sensor 1)

DTC P2241 Oxygen (A/F) Sensor Pumping Current Circuit Low (Bank 2 Sensor 1)

DTC P2242 Oxygen (A/F) Sensor Pumping Current Circuit High (Bank 2 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)

DTC P2255 Oxygen (A/F) Sensor Reference Ground Circuit Low (Bank 2 Sensor 1)

DTC P2256 Oxygen (A/F) Sensor Reference Ground Circuit High (Bank 2 Sensor 1)

Description DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256

HINT:

  1. Although the DTC titles say oxygen sensor, these DTCs relate to the Air Fuel ratio (A/F) sensor.
  2. Sensor 1 refers to the sensor mounted in front of the Three-Way Catalytic Converter (TWC) and located near the engine assembly.

The A/F sensor, which is located between the exhaust manifold and catalyst, consists of alloyed metal elements and a heater.

Depending on the engine operating conditions, the heater heats the sensor elements to activate them. Battery voltage is applied to the heater, and the sensor ground is controlled by the ECM using a duty ratio.

The sensor elements convert the oxygen concentration in the exhaust gas into voltage values to output. Based on the voltage, the ECM determines the air fuel ratio and regulates the fuel injection volume depending on the air fuel ratio and engine operating conditions. The voltage changes between 0.6 V and 4.5 V while the engine is running. If the air fuel ratio is lean, which means the oxygen concentration in the exhaust gas is high, the voltage is high. If the air fuel ratio is rich, which means the oxygen concentration in the exhaust gas is low, the voltage is low.

Description DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE
Description DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE
DTC Code DTC Detection Condition Trouble Area
P2237 P2240 An open in the circuit between terminals A1A+/A2A+ and A1A-/A2A- of the A/F sensor while the engine is running (2 trip detection logic).
  1. Open in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. ECM
P2238 P2241 Any of the following conditions are met (2 trip detection logic):
  1. The A/F sensor output drops while the engine is running.
  1. The voltage at terminal A1A+/A2A+ is 0.5 V or less.
  1. The voltage difference between terminals A1A+/A2A+ and A1A-/A2A- is 0.1 V or less.
  1. Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. ECM
P2239 P2242 The A1A+/A2A+ voltage is higher than 4.5 V (2 trip detection logic).
  1. Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. ECM
P2252 P2255 The A1A-/A2A- voltage is 0.5 V or less (2 trip detection logic).
  1. Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. ECM
P2253 P2256 The A1A-/A2A- voltage is higher than 4.5 V (2 trip detection logic).
  1. Open or short in A/F sensor (bank 1, 2 sensor 1) circuit
  2. A/F sensor (bank 1, 2 sensor 1)
  3. ECM

Monitor description

These DTCs are stored when there is an open or short in the A/F sensor circuit, or if A/F sensor output drops. To detect these problems, the voltage of the A/F sensor is monitored when turning the ignition switch to ON, 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 A/F sensor is between 0.6 V and 4.5 V, it is considered normal. If the voltage is out of the specified range, or the admittance is less than the standard value, the ECM will determine that there is a malfunction in the A/F sensor. If the same malfunction is detected in next driving cycle, the MIL will be illuminated and a DTC will be stored.

Wiring diagram

Refer to DTC P2195.

Confirmation driving pattern

  1. Start the engine and wait for 5 minutes or more.

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 (A/F) sensor, Heated Oxygen (HO2) 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 intelligent tester.

  1. Connect the intelligent tester to the DLC3.
  2. Start the engine and turn the tester on.
  3. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
  4. On the tester, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F sensor.
  5. Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).
  6. Monitor the output voltages of the A/F and HO2 sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the tester.

HINT:

  1. 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%.
  2. Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Tester Display (Sensor) Injection Volume Status Voltage
AFS Voltage B1S1 or AFS Voltage B2S1 (A/F) +25% Rich less than 3.1 V
AFS Voltage B1S1 or AFS Voltage B2S1 (A/F) -12.5% Lean more than 3.4 V
O2S B1S2 or O2S B2S2 (HO2) +25% Rich more than 0.55 V
O2S B1S2 or O2S B2S2 (HO2) -12.5% Lean less than 0.4 V

NOTICE:

The Air Fuel ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen (HO2) sensor has a maximum output delay of approximately 20 seconds.

Case A/F Sensor (Sensor 1) Output Voltage HO2 Sensor (Sensor 2) Output Voltage Main Suspected Trouble Area
1 DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE -
2 DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE
  1. A/F sensor
  2. A/F sensor heater
  3. A/F sensor circuit
3 DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE
  1. HO2 sensor
  2. HO2 sensor heater
  3. HO2 sensor circuit
4 DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FEDTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE
  1. Injector
  2. Fuel pressure
  3. Gas leakage from exhaust system (air fuel ratio extremely rich or lean)
  1. Following the Control the Injection Volume for A/F sensor procedure enables technicians to check and graph the voltage outputs of both the A/F and HO2 sensors.
  2. 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 or AFS Voltage B2S1 and O2S B2S2.

HINT:

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.

1.CHECK HARNESS AND CONNECTOR (A/F SENSOR - ECM)

Disconnect the Air Fuel ratio (A/F) sensor connector. DTC P2237 P2238 P2239 P2240 P2241 P2242 P2252 P2253 P2255 P2256 Land Cruiser 1GR-FE

  1. Disconnect the Air Fuel ratio (A/F) sensor connector.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:

    Tester Connection Switch Condition Specified Condition
    C22-2 (+B) - Body ground Ignition switch ON 11 to 14 V
    C23-2 (+B) - Body ground Ignition switch ON 11 to 14 V

  1. Turn the ignition switch off.

  1. Disconnect the ECM connector.

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

    Standard Resistance (Check for Open):

    for LHD
    Tester Connection Condition Specified Condition
    C22-1 (HA1A) - C45-86 (HA1A) Always Below 1 ?
    C22-3 (A1A+) - C45-93 (A1A+) Always Below 1 ?
    C22-4 (A1A-) - C45-116 (A1A-) Always Below 1 ?
    C23-1 (HA2A) - C45-109 (HA2A) Always Below 1 ?
    C23-3 (A2A+) - C45-120 (A2A+) Always Below 1 ?
    C23-4 (A2A-) - C45-119 (A2A-) Always Below 1 ?
    for RHD
    Tester Connection Condition Specified Condition
    C22-1 (HA1A) - C46-86 (HA1A) Always Below 1 ?
    C22-3 (A1A+) - C46-93 (A1A+) Always Below 1 ?
    C22-4 (A1A-) - C46-116 (A1A-) Always Below 1 ?
    C23-1 (HA2A) - C46-109 (HA2A) Always Below 1 ?
    C23-3 (A2A+) - C46-120 (A2A+) Always Below 1 ?
    C23-4 (A2A-) - C46-119 (A2A-) Always Below 1 ?

    Standard Resistance (Check for Short):

    for LHD
    Tester Connection Condition Specified Condition
    C22-1 (HA1A) or C45-86 (HA1A) - Body ground Always 10 k? or higher
    C22-3 (A1A+) or C45-93 (A1A+) - Body ground Always 10 k? or higher
    C22-4 (A1A-) or C45-116 (A1A-) - Body ground Always 10 k? or higher
    C23-1 (HA2A) or C45-109 (HA2A) - Body ground Always 10 k? or higher
    C23-3 (A2A+) or C45-120 (A2A+) - Body ground Always 10 k? or higher
    C23-4 (A2A-) or C45-119 (A2A-) - Body ground Always 10 k? or higher
    for RHD
    Tester Connection Condition Specified Condition
    C22-1 (HA1A) or C46-86 (HA1A) - Body ground Always 10 k? or higher
    C22-3 (A1A+) or C46-93 (A1A+) - Body ground Always 10 k? or higher
    C22-4 (A1A-) or C46-116 (A1A-) - Body ground Always 10 k? or higher
    C23-1 (HA2A) or C46-109 (HA2A) - Body ground Always 10 k? or higher
    C23-3 (A2A+) or C46-120 (A2A+) - Body ground Always 10 k? or higher
    C23-4 (A2A-) or C46-119 (A2A-) - Body ground Always 10 k? or higher
  NG  
REPAIR OR REPLACE HARNESS OR CONNECTOR
 
OK  
   

2.REPLACE AIR FUEL RATIO SENSOR

  1. Replace the air fuel ratio sensor .

NEXT  
   

3.PERFORM CONFIRMATION DRIVING PATTERN
NEXT  
   

4.CHECK WHETHER DTC OUTPUT RECURS

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON and turn the tester on.

  1. Clear the DTCs .

  1. Start the engine.

  1. Allow the engine to idle for 5 minutes or more.

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

  1. Read the pending DTCs.

    Result
    Result Proceed to
    No output A
    P2237, P2240, P2238, P2241, P2239, P2242, P2252, P2255, P2253 or P2256 output B
  B  
REPLACE ECM
 
A  
   
END