DTC Troubleshooting

Step	Action	Yes	No
1	Was "Engine and Emission Control System Check" performed?	Go to Step 2.	Go to ENGINE AND EMISSION CONTROL SYSTEM CHECK .
2	DTC check Check DTC. Is there DTC(s) other than P2096 and P2097?	Go to applicable DTC(s).	Go to Step 3.
3	HO2S signal check Turn OFF ignition switch and connect scan tool. Warm up engine to normal operating temperature and keep it at 2, 000 r/min. for 60 sec. Repeat racing engine (Depress and release accelerator pedal 5 to 6 times repeatedly to enrich and lean A/F mixture). Check for HO2S output voltage displayed on scan tool. Does HO2S output voltage indicates approx. 0 V for a few seconds, then approx. 0.7 V?	Intermittent trouble. Check for intermittent trouble. Refer to INTERMITTENT AND POOR CONNECTION INSPECTION .	Go to Step 4.
4	Intake system and exhaust system for leakage check Check intake system and exhaust system for leakage. Are intake system and exhaust system in good condition?	Go to Step 5.	Repair or replace defective parts.
5	Fuel injectors and its circuit check Check each fuel injectors and its circuit. Refer to FUEL SYSTEM INSPECTION . Is check result satisfactory?	Go to Step 6.	Repair or replace defective fuel injector or wire harness.
6	HO2S signal circuit and ground circuit check Check HO2S signal circuit and ground circuit referring to Step 3 of DTC P0137: O2 Sensor Circuit Voltage Low (Bank 1, Sensor 2); P0138: O2 Sensor Circuit Voltage High (Bank 1, Sensor 2) EVAP-Leak-Check Model . Are they in good condition?	Go to Step 7.	Repair or replace defective wire harness.
7	HO2S heater circuit check Check HO2S heater circuit referring to Step 2 through 3 of DTC P0037: HO2S Heater Control Circuit Low (Bank-1 Sensor-2); P0038: HO2S Heater Control Circuit High (Bank-1 Sensor-2); P0054: HO2S Heater Resistance (Bank-1 Sensor-2) . Are they in good condition?	Go to Step 8.	Repair or replace defective wire harness.
8	HO2S heater check Check heater resistance of HO2S. Refer to HO2S (HEATED OXYGEN SENSOR) ON-VEHICLE INSPECTION . Is HO2S heater in good condition?	Go to Step 9.	Replace HO2S.
9	A/F sensor signal circuit check Check A/F sensor signal circuit referring to Step 3 of DTC P0131: O2 Sensor (HO2S) Circuit Low Voltage (Bank-1 Sensor-1); P0132: O2 Sensor (HO2S) Circuit High Voltage (Bank-1 Sensor-1); P0134: O2 Sensor (HO2S) No Activity Detected (Bank-1 Sensor-1); P2195: O2 Sensor Signal Stuck Lean (Bank-1 Sensor-1); P2196: O2 Sensor Signal Stuck Rich (Bank-1 Sensor-1); P2237: O2 Sensor Positive Current Control Circuit/Open . Are they in good condition?	Go to Step 10.	Repair or replace defective wire harness.
10	A/F sensor heater circuit check Check A/F sensor heater circuit referring to Step 2 through 3 of DTC P0031: HO2S Heater Control Circuit Low (Bank-1 Sensor-1); P0032: HO2S Heater Control Circuit High (Bank-1 Sensor-1) . Are they in good condition?	Go to Step 11.	Repair or replace defective wire harness.
11	A/F sensor check Check for A/F sensor. Refer to A/F (AIR FUEL RATIO) SENSOR ON-VEHICLE INSPECTION . Is check result satisfactory?	Go to Step 12.	Replace A/F sensor.
12	Engine mechanical systems check Check engine mechanical systems. Engine compression: Refer to COMPRESSION CHECK . Valve clearance: Refer to VALVE CLEARANCE INSPECTION AND ADJUSTMENT . Intake and exhaust valve: Refer to VALVE AND VALVE GUIDE INSPECTION . Valve timing: Refer to CAMSHAFT AND TAPPET REMOVAL AND INSTALLATION . Are check result satisfactory?	Go to Step 13.	Repair or replace defective parts.
13	Replace HO2S. Refer to CMP (CAMSHAFT POSITION) SENSOR ON-VEHICLE INSPECTION . Check DTC. Refer to DTC Check . Is DTC P2096 and P2097 still detected?	Substitute a known-good ECM and recheck.	End.