Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR EXHAUST GAS LEAK
1. Allow the engine to idle.
2. Check for exhaust gas leak around the HO2S.
  OK:
  
  No leak from the HO2S.
  
  NG: REPAIR LEAK
  
  OK: Go to next step

CHECK HEATED OXYGEN SENSOR

Fig 1: Fuel-Trim And HO2S Voltage Cross-Reference

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Warm up the engine.
Allow the engine to idle.
Enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor.
Check the O2S B1 S2 (O2S B2 S2) values when the Control the Injection Volume for A/F Sensor is -12.5% (Lean fuel-trim).
Check the O2S B1 S2 (O2S B2 S2) values when the Control the Injection Volume for A/F Sensor is 25% (Rich fuel-trim).

Standard

INJECTION VOLUME REFERENCE

Control the Injection Volume for A/F Sensor	O2S B1 S2 (O2S B2 S2)
-12.5%	Less than 0.2 V
25%	More than 0.8 V

NG: REPLACE HEATED OXYGEN SENSOR

OK: Go to next step

CHECK DTC
1. Clear DTC (see DTC CHECK / CLEAR ).
2. Turn the engine switch Off.
3. Disconnect the battery negative terminal and wait for 1 minute.
4. Connect the battery negative terminal.
5. Start the engine.
  
  Fig 2: Engine Coolant Temperature Driving Pattern
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
6. Perform the drive pattern.
  1. Warm up the engine.
  2. Accelerate the vehicle until 50 mph (80 km/h) and stop the vehicle.
  3. Drive the vehicle by 35 to 50 mph (60 to 80 km/h) for 5 minutes or more.
7. Check DTC.
  OK:
  
  P0606 is not present.
  
  NG: REPLACE ECM
  
  OK: CHECK FOR INTERMITTENT PROBLEMS