DTC Troubleshooting

WARNING: This page is about a different car, the 2006 Suzuki XL-7. However, it is still accessible from the selected car via links, so may be relevant.

DTC DIAGNOSTIC 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	HO2S-1 output voltage check Connect scan tool to DLC with ignition switch turned OFF. Warm up engine to normal operating temperature and keep it at 2000 r/min. for 60 sec. Repeat racing engine (Repeat depressing accelerator pedal 5 to 6 times continuously to enrich A/F mixture and take foot off from pedal to enlean) and check HO2S output voltage displayed on scan tool. Is over 0.6 V and below 0.3 V indicated?	Go to Step 4.	Go to Step 3.
3	HO2S-1 check With ignition switch turned OFF, disconnect HO2S-1 connector. Check for proper connection to HO2S-1 at each terminal. If OK, connect voltmeter "WHT" wire terminal and "BLU" wire terminal of HO2S-1 connector. Start engine and check voltmeter while repeating racing engine. Is over 0.6 V and below 0.3 V indicated?	"RED" or "GRY/YEL" circuit wire is open or short. If wire and connections are OK, substitute a known-good ECM and recheck.	Replace HO2S-1.
4	Short term fuel trim check Run engine at 2000 r/min. for 60 sec. With engine idling, check short term fuel trim displayed on scan tool. Is it within -20 to +20%?	Intermittent trouble or faulty ECM. Check for intermittent referring to INTERMITTENT AND POOR CONNECTION INSPECTION .	Go to DTC P0171 / P0174: System Too Lean and DTC P0172 / P0175: System Too Rich .