Code P0125: Excessive Time To Enter Closed Loop
NOTE:
For component terminal identification, see TERMINAL IDENTIFICATION
in this article. For appropriate WIRING DIAGRAMS, see WIRING DIAGRAMS
section.
- Disconnect front oxygen sensor connector. Connect test harness (MD998464) to oxygen sensor. Check continuity between terminal No. 1 (Red clip) and No. 3 (Blue clip). If continuity exists, go to next step. If continuity does not exist, replace oxygen sensor.
- Start and warm engine until coolant temperature is 176°F (80°C) or more. Connect jumper wires between battery positive and oxygen sensor terminal No. 1 (Red clip) and between battery negative and terminal No. 3 (Blue clip). Connect DVOM between oxygen sensor terminal No. 2 (Black clip) and No. 4 (White clip). Measure oxygen sensor output voltage, while repeatedly racing engine. If voltage is .6-1.0 volt, go to next step. If voltage is not .6-1.0 volt, replace oxygen sensor.
- Check PCM connector, oxygen sensor connector and wiring harness between oxygen sensor connector and PCM. If wiring and connectors are okay, check fuel injectors. Disconnect fuel injector connector. Measure resistance between fuel injector terminals. If resistance is 2-3 ohms at 68°F (20°C), go to next step. If resistance is not 2-3 ohms at 68°F (20°C), replace fuel injector.
- Using stethoscope, check injector operating sound during cranking or at idle. Check that frequency of operating sound increases as engine RPM increases. If injectors are okay, go to next step. If no operating sound is heard from an injector, check injector drive circuit. If drive circuit is okay, injector or PCM is suspect.
- Check fuel injector connectors, PCM connector and wiring harness between PCM and injector connectors. If wiring and connectors are okay, perform fuel pressure test. See FUEL SYSTEM in BASIC TESTING - 2.0L TURBO article. If fuel pressure is okay, replace PCM.