2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM

420 2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM DTC DTC P200 P203 /F Sensor Circuit Slow Response (ank 1 Sensor 1) /F Sensor Circuit Slow Response (ank 2 Sensor 1) DCRIPTION DTC P200 indicates malfunctions related to the bank 1 /F sensor. DTC P203 indicates malfunctions related to the bank 2 /F sensor. ank 1 refers to the bank that includes No. 1 cylinder. ank 2 refers to the bank that includes No. 2 cylinder. Sensor 1 refers to the sensor mounted in front of the Three-Way Catalytic Converter (TWC) and is located near the engine assembly. Refer to DTC P2195 (See page -364). DTC No. DTC Detection Condition Trouble rea P200 P203 Calculated test value for ir Fuel Ratio (/F) sensor response rate deterioration level is less than threshold. Open or short in ir Fuel Ratio (/F) sensor (sensor 1) circuit ir Fuel Ratio (/F) sensor (sensor 1) ECM MONITOR DCRIPTION fter engine is warmed up, the ECM performs air fuel ratio feedback control to regulate the air fuel ratio at stoichiometric ratio. In addition, this vehicle performs ctive ir Fuel Ratio (/F) Control for approximately 10 seconds after preconditions are met in order to measure the /F sensor response rate. During active air fuel ratio control, the ECM forcibly increases and decreases the injection volume a certain amount based on learned stoichiometric air fuel ratio during usual air fuel feedback control, and measures the /F sensor response rate. The ECM receives a signal from the /F sensor while performing active /F control and uses it to calculate the /F sensor response rate deterioration level. If the test value for /F sensor response rate deterioration level is less than the threshold, the ECM interprets this as a malfunction, and sets the DTC. ir Fuel Ratio Sensor 10 Seconds ON ctive /F Control OFF Normal Malfunction /F Sensor Output Fuel Increase Decrease 115363E02

2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM 421 MONITOR STRTEGY Related DTCs Required Sensors/Components (Main) Frequency of Operation Duration MIL Operation Sequence of Operation P200: ir fuel ratio (/F) sensor (bank 1) slow response P203: ir fuel ratio (/F) sensor (bank 2) slow response /F sensor Once per driving cycle 10 to 15 seconds 2 driving cycles None TYPICL ENLING CONDITIONS P0031, P0032, P0051, P0052 (/F sensor heater - Sensor 1) P0100 - P0103 (MF meter) P0110 - P0113 (IT sensor) P0115 - P0118 (ECT sensor) P0120 - P0223, P2135 (TP sensor) P0125 (Insufficient ECT for Closed Loop) P0171, P0172 (Fuel system) P0300 - P0308 (Misfire) Monitor runs whenever following DTCs not present P0335 (CKP sensor) P0455, P0456 (EVP system) P0500 (VSS) P2196, P2198 (/F sensor - rationality) P2237, P2240 (/F sensor - open) P2440 (IR control valve stuck open) P2441 (IR control valve stuck close) P2444 (IP stuck ON) P2445 (IP stuck OFF) ctive /F control Performing ctive /F control is performed when the following conditions set - attery Voltage 11 V or more ECT 75 C (167 F) or more Idle OFF Engine RPM Less than 4,000 rpm /F sensor status ctivated Fuel cut OFF Engine load 10 to 70 % Shift position 2nd or more Catalyst monitor Not executing Intake air amount 2.5 to 12 g/sec. TYPICL MLFUNCTION THRHOLDS Response rate deterioration level Less than 0.2 V MONITOR RULT Detailed information on CHECKING MONITOR STTUS (See page -17). CONFIRMTION DRIVING PTTERN Performing this confirmation pattern will activate the air fuel ratio (/F) sensor response monitor.

422 2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM Vehicle Speed etween 25 and 75 mph (40 and 120 km/h) [H] Idling [G] Ignition Switch OFF Warming up 3 minutes Time 115372E43 1. Connect the intelligent tester to the DLC3 with CN VIM []. 2. Turn the ignition switch ON []. 3. Turn the tester ON [C]. 4. Clear DTCs (if set) (See page -35) [D]. 5. Enter the following menus: DIGNOSIS / ENHNCED OD II / MONITOR INFO / MONITOR RULT [E]. 6. Check that R RTE 1 S1 is INCOMPL [F]. 7. Start the engine and warm it up [G]. 8. Drive the vehicle at between 25 mph and 75 mph (40 km/h and 120 km/h) for 3 minutes. However, the vehicle should be driven at a constant speed [H]. 9. Check the monitor result values on the intelligent tester by entering the following menus: DIGNOSIS / ENHNCED OD II / MONITOR INFO / TT RULT [I]. 10.If the values indicated on the tester do not change, perform REDINS MONITOR DRIVE PTTERN for the /F sensor and the heated oxygen sensor (See page -20) [J]. Completion of all /F sensor monitors are required to change the value in TT RULT. 11.Note the value of the Monitor Result [K]. 12.Enter the following menus: DIGNOSIS / ENHNCED OD II / DTC INO / PENDING COD [L]. 13.Check if any pending DTCs are set [M]. WIRING DIGRM Refer to DTC P2195 (See page -368). INSPECTION PROCEDURE Intelligent tester only: Malfunctioning areas can be identified by performing the /F CONTROL function provided in the CTIVE TT. The /F CONTROL function can help to determine whether the ir Fuel Ratio (/F) sensor, Heated Oxygen (HO2) sensor and other potential trouble areas are malfunctioning. The following instructions describe how to conduct the /F CONTROL operation using the intelligent tester. 1. Connect the intelligent tester to the DLC3 with CN VIM.

2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM 423 2. Start the engine and turn the tester ON. 3. Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds. 4. On the intelligent tester, enter the following menus: DIGNOSIS / ENHNCED OD II / CTIVE TT / /F CONTROL. 5. Perform the /F CONTROL 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 /F and HO2 sensors (FS 1S1 (FS 2S1) and O2S 1S2 (O2S 2S2)) displayed on the tester. The /F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection volume by 25 %. Each sensor reacts in accordance with increases and decreases in the fuel injection volume. Standard: Tester Display (Sensor) FS 1S1 (FS 2S1) (/F) FS 1S1 (FS 2S1) (/F) O2S 1S2 ( O2S 2S2) (HO2) O2S 1S2 (O2S 2S2) (HO2) Status Voltage Rich Less than 3.0 Lean More than 3.35 Rich More than 0.55 Lean Less than 0.4 NOTICE: The ir Fuel Ratio (/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 /F Sensor (Sensor 1) HO2 Sensor (Sensor 2) Main Suspected Trouble rea 1 More than 3.35 V Less than 3.0 V More than 0.55 V Less than 0.4 V - 2 3 lmost no reaction More than 3.35 V Less than 3.0 V /F sensor More than 0.55 V Less than 0.4 V /F sensor heater /F sensor circuit HO2 sensor lmost no reaction HO2 sensor heater HO2 sensor circuit 4 Injection volume lmost no reaction lmost no reaction Fuel injector Fuel pressure Gas leakage from exhaust system (ir fuel ratio extremely lean or rich)

424 2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM Following the /F CONTROL procedure enables technicians to check and graph the voltage outputs of both the /F and HO2 sensors. To display the graph, enter the following menus: DIGNOSIS / ENHNCED OD II / CTIVE TT / /F CONTROL / USER DT / FS 1S1 and O2S 1S2 or FS 2S1 and O2S 2S2. Then press the Y button and ENTER button, followed by the F4 button. DTC P200 may be also set when the air fuel ratio is stuck rich or lean. low /F sensor voltage could be caused by a rich air fuel mixture. Check for conditions that would cause the engine to run rich. high /F sensor voltage could be caused by a lean air fuel mixture. Check for conditions that would cause the engine to run lean. 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 be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air/fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction. 1 CHECK NY OTHER DTCS OUTPUT (IN DDITION TO DTC P200 ND/OR P203) Result (c) (d) Connect the intelligent tester to the DLC3 with CN VIM. Turn the ignition switch ON and turn the tester ON. Enter the following menus: DIGNOSIS / ENHNCED OD II / DTC INFO / CURRENT COD. Read DTCs. Display (DTC Output) P200 and/or P203 P200 and/or P203 and other DTCs Proceed to If any DTCs other than P200 and/or P203 are output, troubleshoot those DTCs first. GO TO DTC CHRT 2 INSPECT IR FUEL RTIO SENSOR (HETER RISTNCE) Component Side /F Sensor 12 + HT 13 F- F+ Front View OK 085152E60 (c) NG Disconnect the 12 or 13 ir Fuel Ratio (/F) sensor connector. Measure the resistance of the /F sensor connector. Standard resistance Tester Connection Specified Condition HT (1) - + (2) 1.8 to 3.4 Ω at 20 C (68 F) HT (1) - F- (4) 10 kω or higher Reconnect the /F sensor connector. REPLCE IR FUEL RTIO SENSOR

2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM 425 3 CHECK HRNS ND CONNECTOR (/F SENSOR - ECM) Wire Harness Side 12 /F Sensor Connector 13 HT + (c) Disconnect the 12 or 13 /F sensor connector. Turn the ignition switch ON. Measure the voltage between the + terminal of the /F sensor connector and body. Standard voltage Tester Connection Specified Condition + (2) - ody 10 V or more F+ F- Front View ECM Connector E5 (d) (e) (f) Turn the ignition switch OFF. Disconnect the E5 ECM connector. Measure the resistance. Standard resistance (Check for open) Tester Connection Specified Condition HT (12-1) - H1 (E5-2) HT (13-1) - H2 (E5-1) H2 H1 2+ 2-1+ 1-115727E02 F+ (12-3) - 1+ (E5-22) F+ (13-3) - 2+ (E5-23) F- (12-4) - 1- (E5-30) F- (13-4) - 2- (E5-31) Standard resistance (Check for short) elow 1 Ω Tester Connection HT (12-1) or H1 (E5-2) - ody HT (13-1) or H2 (E5-1) - ody F+ (12-3) or 1+ (E5-22) - ody F+ (13-3) or 2+ (E5-23) - ody F- (12-4) or 1- (E5-30) - ody F- (13-4) or 2- (E5-31) - ody Specified Condition 10 kω or higher

426 2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM Reference (ank 1 Sensor 1 System Diagram) From attery /F Heater Fuse /F HETER /F Sensor Heater + HT H1 Sensor F- F+ 1+ 1- ECM Duty Control From EFI Relay 118002E16 (g) (h) Reconnect the /F sensor connector. Reconnect the ECM connector. NG REPIR OR REPLCE HRNS OR CONNECTOR OK 4 PERFORM CONFIRMTION DRIVING PTTERN NEXT 5 CHECK WHETHER DTC OUTPUT RECURS (DTC P200 ND/OR P203) Result Read DTCs using the intelligent tester. Enter the following menus: DIGNOSIS / ENHNCED OD II / DTC INFO / PENDING COD. Display (DTC Output) P200 and/or P203 No output Proceed to CHECK FOR INTERMITTENT PROLEMS

2UZ-FE ENGINE CONTROL SYSTEM SFI SYSTEM 427 6 REPLCE IR FUEL RTIO SENSOR NEXT 7 PERFORM CONFIRMTION DRIVING PTTERN NEXT 8 CHECK WHETHER DTC OUTPUT RECURS (DTC P200 ND/OR P203) Result Read DTCs using the intelligent tester. Enter the following menus: DIGNOSIS / ENHNCED OD II / DTC INFO / PENDING COD. Display (DTC Output) P200 and/or P203 No output Proceed to CHECK EXTREMELY RICH OR LEN CTUL IR FUEL RTIO (REFER TO DTC P0171 PROCEDURE) END