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Home >> Lexus >> 2002 >> IS 300 Base, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 103 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P0134: Oxygen Sensor Circuit No Activity Detected (Bank 1 Sensor 1) Or DTC P0154: Oxygen Sensor Circuit No Activity Detected (Bank 2 Sensor 1) >> Diagnostic Aids
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Diagnostic Aids

WARNING: This page is about a different car, the 2003 Lexus GX 470. However, it is still accessible from the selected car via links, so may be relevant.
  1. Bank No. 1 refers to bank which includes cylinder No. 1. Bank No. 2 refers to bank without cylinder No. 1. Heated oxygen sensor No. 1 refers to sensor closest to engine block.
  2. With hand-held tester it is possible to narrow down the trouble area by performing the following:
    • Connect hand-held tester to DLC3 on vehicle. See Figure.
    • Turn ignition switch on.
    • Warm up engine with engine speed at 2500 RPM for about 90 seconds.
    • Select "DIAGNOSIS/ENHANCED OBD II/ACTIVE TEST/ A/F CONTROL".
    • Perform "A/F CONTROL" when idle condition (press right or left button). There is a few seconds delay in sensor 1 (front sensor) output. There is about 20 seconds delay in sensor 2 (rear sensor). Heated oxygen sensor reacts according to increase and decrease of injection volume. +25 percent goes to rich output: more than .55 volt -12.5 percent goes to lean output: less than .4 volt.
    • To show a graph indication of heated oxygen sensor output, select and push "YES or NO" button 2 data "O2S B1S1 and O2 B1S2" or "O2S B2S1 and O2S B2S2" and press button "4" after selecting "ACTIVE TEST/ A/F CONTROL/USER DATA". If the vehicle is short of fuel, air-fuel ratio becomes lean, heated oxygen sensor DTCs will be recorded and MIL becomes illuminated.
  3. If different DTCs related to different systems are output together while ECM terminal E2 is used as a ground terminal, ECM terminal E2 may be open. Repair as necessary. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
  4. Read freeze frame data using hand-held tester or OBD-II scan tool, as freeze frame data records engine conditions when a malfunction is detected. When troubleshooting, this is useful for determining whether vehicle was running or stopped, engine was warmed up or not, or air-fuel ratio was lean or rich at time of malfunction.
  5. A high heated oxygen sensor (sensor 1) voltage (0.55 volt or more) could be caused by a rich air fuel mixture. Check for conditions that would cause engine to run rich. A low heated oxygen sensor (sensor 1) voltage (0.4 volt or less) could be caused by a lean air fuel mixture. Check for conditions that would cause engine to run lean.
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