P2242
1GR-FE ENGINE CONTROL SYSTEM: SFI SYSTEM: P2237-P2239,P2240-P2242,P2252,P2253,P2255,P2256: Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1)
DESCRIPTION
Refer to DTC P2195 P2195.
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 ignition switch to the on position, 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 0.6 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 air fuel ratio sensor. If the same malfunction is detected in next driving cycle, the MIL will be illuminated and a DTC will be stored.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
P2237 and P2240 (Air Fuel Ratio Sensor Open Circuit Between A1A+ and A1A-/A2A+ and A2A-)
P2238 and P2241 (Air Fuel Ratio Sensor Low Impedance)
Other
TYPICAL MALFUNCTION THRESHOLDS
P2237 and P2240 (Air Fuel Ratio Sensor Open Circuit Between A1A+ and A1A-/A2A+ and A2A-)
P2238 and P2241 (Air Fuel Ratio Sensor Low Impedance)
P2238 and P2241 (Air Fuel Ratio Sensor Short Circuit Between A1A+ and GND/A2A+ and GND)
P2239 and P2242 (Air Fuel Ratio Sensor Short Circuit Between A1A+ and +B/A2A+ and +B)
P2252 and P2255 (Air Fuel Ratio Sensor Short Circuit Between A1A- and GND/A2A- and GND)
P2253 and P2256 (Air Fuel Ratio Sensor Short Circuit Between A1A- and +B/A2A- and +B)
P2238 and P2241 (Air Fuel Ratio Sensor Short Circuit Between A1A+ and A1A-/A2A+ and A2A-)
COMPONENT OPERATING RANGE
CONFIRMATION DRIVING PATTERN
1. Connect the Techstream to the DLC3.
2. Turn the ignition switch to ON and turn the Techstream on.
3. Clear DTCs (even if no DTCs are stored, perform the clear DTC operation).
4. Turn the ignition switch off and wait for at least 30 seconds.
5. Turn the ignition switch to ON and turn the Techstream on.
6. Start the engine and wait 5 minutes.
7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
8. Read pending DTCs.
HINT
* If a pending DTC is output, the system is malfunctioning.
* If a pending DTC is not output, perform the following procedure.
9. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
10. Input the DTC: P2237, P2238, P2239, P2240, P2241, P2242, P2252, P2253, P2255 or P2256.
11. Check the DTC judgment result.
HINT
* If the judgment result shows NORMAL, the system is normal.
* If the judgment result shows ABNORMAL, the system has a malfunction.
* If the judgment result shows INCOMPLETE or UNKNOWN, idle the engine for 5 minutes and check the DTC judgment result again.
12. If no pending DTC is output, perform a universal trip and check for permanent DTCs DTC Check / Clear.
HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.
WIRING DIAGRAM
Refer to DTC P2195 P2195.
INSPECTION PROCEDURE
HINT
Malfunctioning areas can be identified by performing the Control the Injection Volume function provided in the Active Test. The Control the Injection Volume function can help to determine whether the air-fuel ratio sensor, heated oxygen sensor and other potential trouble areas are malfunctioning.
The following instructions describe how to conduct the Control the Injection Volume operation using the Techstream.
1. Connect the Techstream to the DLC3.
2. Start the engine and turn the Techstream on.
3. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
4. Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume.
5. Perform the Active Test operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume).
6. Monitor the output voltages of the air fuel ratio sensor and heated oxygen sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the Techstream.
HINT
* Change the fuel injection volume within the range of -12% to +12%. The injection volume can be changed in fine gradations within this range.
* Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Standard Voltage:
NOTICE:
The Air-Fuel Ratio sensor has an output delay of a few seconds and the Heated Oxygen sensor has a maximum output delay of approximately 20 seconds.
- Following the Control the Injection Volume procedure enables technicians to check and graph the voltage outputs of both the air fuel ratio and heated oxygen sensors.
- To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume / AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2; and then press the graph button on the Data List view.
NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
PROCEDURE
1. CHECK HARNESS AND CONNECTOR (AIR FUEL RATIO SENSOR - ECM) P0171
NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.
2. REPLACE AIR FUEL RATIO SENSOR
(a) Replace the air-fuel ratio sensor Removal.
NEXT -- Continue to next step.
3. CHECK WHETHER DTC OUTPUT RECURS
(a) Connect the Techstream to the DLC3.
(b) Turn the ignition switch to ON.
(c) Turn the Techstream on.
(d) Clear DTCs DTC Check / Clear.
(e) Turn the ignition switch off and wait for at least 30 seconds.
(f) Turn the ignition switch to ON.
(g) Turn the Techstream on.
(h) Drive the vehicle in accordance with the driving pattern described in the Confirmation Driving Pattern.
(i) Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.
(j) Input the DTC: P2237, P2238, P2239, P2240, P2241, P2242, P2252, P2253, P2255 or P2256.
(k) Check the DTC judgment.
Result
B -- REPLACE ECM Removal
A -- END