Diagnosis & Repair
WARNING: This page is about a different car, the 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
- If other DTCs are displayed, diagnose and repair those DTCs first and retest system. If only DTC P1133 and/or P1153 is displayed, go to next step.
- Connect scan tool to Data Link Connector (DLC) No. 3. Start engine and raise engine speed to 2500 RPM for approximately 90 seconds. Using scan tool, monitor each A/F sensor output voltage. See AIR/FUEL SENSOR OUTPUT VOLTAGE SPECIFICATIONS table. If voltage is as specified, go to next step. If voltage is not as specified, go to step 8.AIR/FUEL SENSOR OUTPUT VOLTAGE SPECIFICATIONS
Application & Operating Condition Specification Using OBD-II Scan Tool Engine Idling, Engine Racing & Driving Vehicle (1) (2) Using Lexus Scan Tool Engine Idling, Engine Racing & Driving Vehicle (1) (3) (1) Drive vehicle at 25 MPH or more with engine speed of 1500 RPM or more while opening and closing the throttle. (2) Voltage should not remain at .56 volt or less, .66 volt, or .76 volt or more. (3) Voltage should not remain at 2.80 volts or less, 3.30 volts, or 3.80 volts or more. - Check for open or short in wiring between ECM and suspect A/F sensor. See WIRING DIAGRAMS article. If problem exists, repair wiring as necessary. If problem does not exist, go to next step.
- Disconnect suspect A/F sensor harness connector. One A/F sensor is located in each exhaust manifold. Measure resistance between terminal B+ (Black/Red wire) and HT (Blue wire on bank No. 1 or Green wire on bank No. 2) at A/F sensor connector (component side). Resistance should be .8-1.4 ohms at 68°F (20°C) or 1.8-3.2 ohms at 1472°F (800°C). If resistance is not as specified, replace appropriate A/F sensor. If resistance is as specified, go to next step.
- Ensure oil dipstick, oil filler cap, PCV system and all other air induction system components are intact and operating properly. If problem exists, repair as necessary. If problem does not exist, go to next step.
- Check fuel pressure. See FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. If fuel pressure is not within specification, repair as necessary. If fuel pressure is within specification, go to next step.
- Check fuel injectors. See FUEL SYSTEM in SYSTEM & COMPONENT TESTING article. If problem exists, repair as necessary. If problem does not exist, replace defective A/F sensor.
- Clear DTCs. Perform test drive confirmation, then go to next step. See TEST DRIVE CONFIRMATION .
- Recheck for DTCs. If DTCs P1133 and/or P1153 is displayed again, replace ECM. If DTCs P1133 and P1153 are not displayed again, vehicle either ran out of fuel or problem is intermittent. Check component and ECM connections.