209 DTC DTC P0420 P0430 Catalyst System Efficiency elow Threshold (ank 1) Catalyst System Efficiency elow Threshold (ank 2) MONITOR DCRIPTION The ECM uses senss mounted in front of and behind the Three-Way Catalytic Converter (TWC) to monit its efficiency. The first sens, the ir-fuel Ratio (/F) sens, sends pre-catalyst infmation to the ECM. The second sens, the Heated Oxygen sens, sends post-catalyst infmation to the ECM. In der to detect any deteriation in the TWC, the ECM calculates the Oxygen Stage Capacity (OSC) of the TWC. This calculation is based on the voltage output of the HO2 sens while perfming active airfuel ratio control, rather than the conventional detecting method, which uses the locus ratio. The OSC value is an indication of the oxygen stage capacity of the TWC. When the vehicle is being driven with a warm engine, active air-fuel ratio control is perfmed f approximately 15 to 20 seconds. When it is perfmed, the ECM deliberately sets the air-fuel ratio to lean rich levels. If a rich-lean cycle of the HO2 sens is long, the OSC becomes greater. There is a direct crelation between the OSCs of the HO2 sens and the TWC. The ECM uses the OSC value to determine the state of the TWC. If any deteriation has occurred, it illuminates the MIL and sets a DTC. DTC No. DTC Detection Conditions Trouble reas P0420 P0430 OSC value smaller than standard value under active air-fuel ratio control (2 trip detection logic) OSC value smaller than standard value under active air-fuel ratio control (2 trip detection logic) ank 1 refers to the bank that includes cylinder No. 1. ank 2 refers to the bank that does not include cylinder No. 1. Sens 1 refers to the sens closest to the engine assembly. Sens 2 refers to the sens farthest away from the engine assembly. MONITOR STRTEGY /F sens (bank 1 sens 1) HO2 sens (bank 1 sens 2) Exhaust manifold (TWC) /F sens (bank 2 sens 1) HO2 sens (bank 2 sens 2) Exhaust manifold (TWC) Related DTCs Required Senss/Components (Main) Required Senss/Components (Related) Frequency of Operation Duration MIL Operation Sequence of Operation P0420: Catalyst Deteriation P0430: Catalyst Deteriation /F sens and heated oxygen sens Intake air temperature sens, mass air flow meter, crankshaft position sens and engine coolant temperature sens Once per driving cycle 30 seconds me 2 driving cycles None
210 1GR-FE ENGINE CONTROL SYSTEM SFI SYSTEM TYPICL ENLING CONDITIONS P0011 (VVT System 1 - dvance) P0012 (VVT System 1 - Retard) P0021 (VVT System 2 - dvance) P0022 (VVT System 2 - Retard) P0031, P0032, P0051, P0052 (/F sens heater - Sens 1) P0037, P0038, P0057, P0058 (HO2 sens Heater - Sens 2) P0100 - P0103 (MF meter) P0115 - P0118 (ECT sens) P0120 - P0223, P2135 (TP sens) Monit runs whenever following DTCs not present P0125 (Insufficient ECT f closed loop) P0136, P0156 (HO2 Sens - Sens 2) P0171, P0172 (Fuel system) P0300 - P0306 (Misfire) P0335 (CKP sens) P0340 (CMP sens) P0351 - P0356 (Ignit) P0500 (VSS) P2196, P2198 (/F sens - rationality) P200, P203 (/F sens - slow response) attery voltage 11 V me IT -10 C (14 F) me Engine coolant temperature sens 75 C (167 F) me tmospheric pressure coefficient 0.75 me Delay time after IDCE ON Less than 5 seconds Engine RPM Less than 3,200 rpm /F sens status ctivated Fuel system status Closed loop Delay time after fuel cut 10 seconds me Engine load 10 to 70 % ll of the following conditions are met Condition 1, 2 and 3 1. Mass air flow rate 5 to 70 g/sec 2. Front catalyst temperature (estimated) 650 to 840 C (1,202 to 1,544 F) 3. Rear catalyst temperature (estimated) 100 to 900 C (212 to 1,652 F) TYPICL MLFUNCTION THRHOLDS Oxygen Stage Capacity (OSC) of Three-Way Catalytic Converter (TWC) Less than 0.04 g MONITOR RULT Detailed infmation on Checking Monit (See page -19). CONDITIONING FOR SENSOR TTING Perfm the operation with the engine speeds and time durations described below pri to checking the wavefms of the /F and HO2 senss. This is in der to activate the senss sufficiently to obtain the appropriate inspection results.
211 Engine Speed 3,000 rpm (c) (d) 2,000 rpm (d) Idling Ignition Switch OFF (a) (b) Time Warming up t least 3 minutes 2 seconds Check 118003E01 (a) Connect an intelligent tester to the DLC3. (b) Start the engine and warm it up with all the accessies switched OFF, until the engine coolant temperature stabilizes. (c) Run the engine at an engine speed of between 2,500 rpm and 3,000 rpm f at least 3 minutes. (d) While running the engine at 3,000 rpm f 2 seconds and 2,000 rpm f 2 seconds, check the wavefms of the /F and HO2 senss using the tester. If either of the voltage outputs of the ir-fuel Ratio (/F) Heated Oxygen sens does not fluctuate, either of the senss makes a noise, the sens may be malfunctioning. If the voltage outputs of both the senss remain lean rich, the air-fuel ratio may be extremely lean rich. In such cases, perfm the following /F CONTROL using an intelligent tester. If the Three-Way Catalytic Converter (TWC) has deteriated, the HO2 sens (located behind the TWC) voltage output fluctuates up and down frequently, even under nmal driving conditions (active air-fuel ratio control is not perfmed).
212 1GR-FE ENGINE CONTROL SYSTEM SFI SYSTEM Voltage output when active air-fuel ratio control not perfmed Wavefm of /F Sens in front of TWC 3.5 V 3.0 V Nmal Catalyst Deteriated Catalyst Wavefm of HO2 Sens behind TWC 1.0 V 0 V 10 seconds 10 seconds 121610E01 CONDITIONING FOR SENSOR TTING Intelligent tester only: Malfunctioning areas can be identified by perfming the /F CONTROL function provided in the CTIVE TT. The /F CONTROL function can help to determine whether the ir-fuel Ratio (/F) sens, Heated Oxygen sens and other potential trouble areas are malfunctioning. The following instructions describe how to conduct the /F CONTROL operation using an intelligent tester. (1) Connect an intelligent tester to the DLC3. (2) Start the engine and turn the tester ON. (3) Warm up the engine at an engine speed of 2,500 rpm f approximately 90 seconds. (4) Select the following menu items: DIGNOSIS / ENHNCED OD II / CTIVE TT / /F CONTROL. (5) Perfm the /F CONTROL operation with the engine in an idling condition (press the RIGHT LEFT button to change the fuel injection volume). (6) Monit the voltage outputs of the /F and HO2 senss (FS 1S1 and O2S 1S2 FS 2S1 and O2S 2S2) displayed on the tester. The /F CONTROL operation lowers the fuel injection volume by 12.5 % increases the injection volume by 25 %. Each sens reacts in accdance with increases and decreases in the fuel injection volume. Standard Tester Display (Sens) FS 1S1 FS 2S1 (/F) FS 1S1 FS 2S1 (/F) O2S 1S2 O2S 2S2 O2S 1S2 O2S 2S2 Injection Volumes Voltages Rich Less than 3.0 Lean Me than 3.35 Rich Me than 0.55 Lean Less than 0.4
213 NOTICE: The ir-fuel Ratio (/F) sens has an output delay of a few seconds and the Heated Oxygen sens has a maximum output delay of approximately 20 seconds. Case /F Sens (Sens 1) Output Voltage HO2 Sens (Sens 2) Output Voltage Main Suspected Trouble reas 1 Me than 3.35 V Less than 3.0 V Me than 0.55 V Less than 0.4 V - 2 lmost /F sens Me than 0.55 V Less than 0.4 V /F sens heater /F sens circuit 3 Me than 3.35 V Less than 3.0 V HO2 sens HO2 sens heater HO2 sens circuit lmost 4 lmost lmost Inject Fuel pressure Gas leakage from exhaust system (ir-fuel ratio extremely lean rich) Following the /F CONTROL procedure enables technicians to check and graph the voltage outputs of both the /F and HO2 senss. To display the graph, select the following menu items on the tester: DIGNOSIS / ENHNCED OD II / CTIVE TT / /F CONTROL / USER DT / FS 1S1 and O2S 1S2 FS 2S1 and O2S 2S2, and press the Y button and then the ENTER button followed by the F4 button. Read freeze frame data using an intelligent tester. Freeze frame data recd the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving stationary, if the engine was warmed up not, if the air-fuel ratio was lean rich, and other data, from the time the malfunction occurred. 1 CHECK NY OTHER DTCS OUTPUT (IN DDITION TO DTC P0420 ND/OR P0430) Result (a) Connect an intelligent tester to the DLC3. (b) Turn the ignition switch ON and turn the tester ON. (c) Select the following menu items: DIGNOSIS / ENHNCED OD II / DTC INFO / CURRENT COD. (d) Read DTCs. Display (DTC Output) P0420 and/ P0430 Proceed To
214 1GR-FE ENGINE CONTROL SYSTEM SFI SYSTEM Display (DTC Output) P0420 and/ P0430 and other DTCs Proceed To If any DTCs other than P0420 P0430 are output, troubleshoot those DTCs first. GO TO DTC CHRT 2 PERFORM CTIVE TT USING INTELLIGENT TTER (/F CONTROL) Standard (a) Connect an intelligent tester to the DLC3. (b) Start the engine and turn the tester ON. (c) Warm up the engine at an engine speed of 2,500 rpm f approximately 90 seconds. (d) Select the following menu items: DIGNOSIS / ENHNCED OD II / CTIVE TT / /F CONTROL. (e) Perfm the /F CONTROL operation with the engine in an idling condition (press the RIGHT LEFT button to change the fuel injection volume). (f) Monit the voltage outputs of the /F and HO2 senss (FS 1S1 and O2S 1S2 FS 2S1 and O2S 2S2) displayed on the tester. The /F CONTROL operation lowers the fuel injection volume by 12.5 % increases the injection volume by 25 %. Each sens reacts in accdance with increases and decreases in the fuel injection volume. Tester Display (Sens) FS 1S1 FS 2S1 (/F) FS 1S1 FS 2S1 (/F) O2S 1S2 O2S 2S2 O2S 1S2 O2S 2S2 Injection Volumes Voltages Rich Less than 3.0 Lean Me than 3.35 Rich Me than 0.55 Lean Less than 0.4 Result FS 1S1 FS 2S1 O2S 1S2 O2S 2S2 /F Condition and /F and HO2 Senss Conditions Misfires Main Suspected Trouble reas Three-Way Catalytic Converter (TWC) Lean/Rich Lean/Rich Nmal - Lean Lean/Rich /F sens malfunction - /F sens Rich Lean/Rich /F sens malfunction - /F sens Lean/Rich Lean HO2 sens malfunction - Lean/Rich Rich HO2 sens malfunction - HO2 sens HO2 sens Proceed To C
215 FS 1S1 FS 2S1 O2S 1S2 O2S 2S2 /F Condition and /F and HO2 Senss Conditions Misfires Lean Lean ctual air-fuel ratio lean May occur Rich Rich ctual air-fuel ratio rich - Main Suspected Trouble reas Extremely rich lean actual air-fuel ratio Extremely rich lean actual air-fuel ratio Proceed To Lean: During /F CONTROL, the /F sens output voltage (FS) is consistently me than 3.35 V, and the HO2 sens output voltage (O2S) is consistently less than 0.4 V. Rich: During /F CONTROL, the FS is consistently less than 3.0 V, and the O2S is consistently me than 0.55 V. Lean/Rich: During /F CONTROL of the CTIVE TT, the output voltage of the HO2 sens alternates crectly. C CHECK ND REPLCE IR FUEL RTIO SENSOR CHECK ND REPLCE HETED OXYGEN SENSOR, ND CHECK ND REPIR EXHUST GS LEKGE 3 CHECK FOR EXHUST GS LEKGE OK: No gas leakage. NG REPIR OR REPLCE EXHUST GS LEKGE POINT OK REPLCE THREE-WY CTLYTIC CONVERTER