DTC Troubleshooting

NOTE: Before this trouble shooting is performed, read the precautions for DTC troubleshooting referring to PRECAUTIONS FOR DTC TROUBLESHOOTING .

DTC TROUBLESHOOTING CHART

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	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 3.	Repair or replace defective parts.
3	Fuel pressure check Check fuel pressure referring to FUEL PRESSURE CHECK . Is check result satisfactory?	Go to Step 4.	Repair or replace defective parts.
4	Fuel injectors and its circuit check Check fuel injectors referring to FUEL INJECTOR INSPECTION . Is check result satisfactory?	Go to Step 5.	Faulty injection(s) or its circuit.
5	MAF sensor visual inspection Check MAF sensor and air intake system. Objects which block measuring duct and resistor of MAF sensor. Other air flow which does not pass MAF sensor. Are they in good condition?	Go to Step 6.	Repair or replace defective part.
6	MAF sensor for performance check With ignition switch turned OFF, connect scan tool to DLC. Start engine and warm up to normal operating temperature. Check MAF value using scan tool (Refer to SCAN TOOL DATA for normal value). Is each value within specified range?	Go to Step 7.	Go to DTC P0101: MASS AIR FLOW CIRCUIT RANGE/PERFORMANCE .
7	A/F sensor adjusting resistor circuit check Disconnect connectors from A/F sensor (bank-1) and ECM with ignition switch turned OFF. Check for proper terminal connection to A/F sensor (bank-1) connector and ECM connector. If connections are OK, check that A/F sensor (bank-1) adjusting resistor circuit is as follows. Wiring harness resistance of each "Adjusting resistor (+) circuit of A/F sensor (bank-1)" and "Adjusting resistor (-) circuit of A/F sensor (bank-1)" is less than 1 Ω. Insulation resistance between "Adjusting resistor (+) circuit of A/F sensor (bank-1)" and vehicle body ground is infinity. Insulation resistance between "Adjusting resistor (+) circuit of A/F sensor (bank-1)" and "Adjusting resistor (-) circuit of A/F sensor (bank-1)" is infinity. Circuit voltage between "Adjusting resistor (+) circuit of A/F sensor (bank-1)" and vehicle body ground is 0 V with ignition switch tuned ON. Are they in good condition?	Go to Step 8.	Repair or replace defective wiring harness.
8	A/F sensor adjusting resistor check Check for resistance of A/F sensor (bank-1) adjusting resistor referring to AIR FUEL RATIO (A/F) SENSOR ON-VEHICLE INSPECTION . Is check result satisfactory?	Go to Step 9.	Replace A/F sensor (bank-1).
9	Valves and valves clearance check Check bank-1 intake & exhaust valve and valve clearance referring to VALVE LASH (CLEARANCE) INSPECTION and VALVES AND VALVE GUIDES INSPECTION . Is check result satisfactory?	Substitute a known-good ECM and recheck. If ECM OK, replace A/F sensor (bank-1).	Repair or replace defective parts.