Inspection Procedure

1. Allow the engine to idle.
2. Check for exhaust gas leak around the heated oxygen sensor.

   OK: 

   No leak from the heated oxygen sensor. 

NG: REPAIR OR REPLACE EXHAUST GAS LEAKAGE POINT 

OK: Go to next step 

1. Connect Techstream to the DLC3.
2. Start the engine and turn the tester on.
3. Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
4. Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F sensor.
5. Perform the Control the Injection Volume for A/F sensor operation with the engine in an idling condition (press the RIGHT or LEFT button to change the fuel injection volume).
6. Monitor the voltage outputs of the HO2 sensor displayed on the tester.

   HINT:

   • The Control the Injection Volume for A/F sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 25%.
   • Each sensor reacts in accordance with increases in the fuel injection volume.

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard voltage 

NG: REPLACE HEATED OXYGEN SENSOR 

OK: Go to next step 

1. Connect Techstream to the DLC3.
2. Turn the power switch on (IG).
3. Turn the tester on.
4. Clear the DTC.
5. Turn the power switch off.
6. Disconnect the auxiliary battery negative terminal and wait for 1 minute.
7. Connect the auxiliary battery negative terminal.
8. Start the engine.
9. Perform the drive pattern.
   1. Warm up the engine.
   2. Accelerate the vehicle to 50 mph (80 km/h) and stop the vehicle.
   3. Drive the vehicle at 35 to 50 mph (60 to 80 km/h) for 5 minutes or more.
   Fig 2: Monitor Drive Pattern For P0606

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
10. Enter the following menus: Powertrain / Engine / Trouble Code.
11. Read the DTCs.

Result 

B: CHECK FOR INTERMITTENT PROBLEMS 

A: REPLACE HYBRID VEHICLE CONTROL ECU