Inspection Procedure
HINT:
Hand-held tester only:
Narrowing down the trouble area is possible by performing "A/F CONTROL" ACTIVE TEST (heated oxygen sensor or other trouble areas can be distinguished).
HINT:
"A/F CONTROL" is the ACTIVE TEST which changes the injection volume to -12.5 % or +25 %.
- Connect the hand-held tester to the DLC3 on the vehicle.
- Turn the ignition switch ON.
- Warm up the engine by running the engine speed at 2,500 rpm for approximately 90 seconds.
- Select the item "DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL".
- Perform "A/F CONTROL" with the engine in an idle condition (press the right or left button).
Result:
Heated oxygen sensor reacts in accordance with increase and decrease of injection volume +25 % --> rich output: More than 0.5 V, -12.5 % --> lean output: Less than 0.4 V
The following of A/F CONTROL procedure enables the technician to check and graph the voltage outputs of both the heated oxygen sensors.
For displaying the graph indication, enter "ACTIVE TEST/A/F CONTROL/ USER DATA", then select "O2S B1S1 and O2S B1S2" by pressing "YES" button and push "ENTER" button before pressing "F4" button.
HINT:
- If different DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may be open.
- Read freeze frame data using the hand-held tester or the OBDII scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.
- CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0136)
- Connect the hand-held tester or the OBD II scan tool to the DLC3.
- Turn the ignition switch ON and push the hand-held tester or the OBD II scan tool main switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES".
- Read the DTCs.
Result:
RESULT REFERENCEDisplay (DTC output) Proceed to P0136 A P0136 and other DTCs B
HINT:
If any other codes besides P0136 are output, perform the troubleshooting for those DTCs first.
- B : GO TO RELEVANT DIAGNOSTIC TROUBLE CODE CHART
- A : Go to next Step
- READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL (OUTPUT VOLTAGE OF HEATED OXYGEN SENSOR)
- Connect the hand-held tester or the OBD II scan tool to the DLC3.
- Start the engine and push the hand-held tester or the OBD II scan tool main switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / O2S B1S2".
- After warming up the engine, run the engine at 2,500 rpm for 3 minutes.
- Read the output voltage of the heated oxygen sensor (sensor 2) when the engine rpm is suddenly increased.
HINT:
Quickly accelerate the engine to 4,000 rpm 3 times by using the accelerator pedal.
Standard:
The output voltage of heated oxygen sensor (sensor 2): Alternates from 0.4 V or less to 0.5 V or more.
- OK : Go to step 6
- NG : go to next step
- INSPECT HEATED OXYGEN SENSOR (HEATER RESISTANCE)
- Disconnect the H8 heated oxygen sensor connector.
- Measure the resistance between the terminals of the heated oxygen sensor connector.
Standard:
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition HT(H8-2)-+B (H8-1) 5 to 10 Ω at 20°C (68°F) HT (H8-2) - E1 (H8-3) 10 kΩ or higher - Reconnect the heated oxygen sensor connector.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- INSPECT EFI RELAY
- CHECK HARNESS AND CONNECTOR (HEATED OXYGEN SENSOR - ECM)
- Disconnect the H8 heated oxygen sensor connector.
- Disconnect the E4 and E5 ECM connector.
- Check the resistance between the wire harness side connectors.
Standard (Check for open):
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition HT (H8-2)-HT1B (E5-4) Below 1 Ω OX (H8-4)-OX1B (E4-21) Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Standard (Check for short):
TESTER CONNECTION AND SPECIFIED CONDITIONTester Connection Specified Condition HT (H8-2) or HT1B (E5-4) - Body ground 10 kΩ or higher OX (H8-4) or OX1B (E4-21) - Body ground - Reconnect the ECM connector.
- Reconnect the heated oxygen sensor connector.
- PERFORM CONFIRMATION DRIVING PATTERN
HINT:
Clear all DTCs prior to performing the confirmation driving pattern.
- READ OUTPUT DTC (DTC P0136 IS OUTPUT AGAIN)
- Connect the hand-held tester or the OBD II scan tool to the DLC3.
- Turn the ignition switch ON and push the hand-held tester or the OBD II scan tool main switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DTC INFO / CURRENT CODES".
- Read the DTCs.
Result:
RESULT REFERENCEDisplay (DTC output) Proceed to P0136 A No output B
- B : CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT PROBLEMS )
- A : REPLACE HEATED OXYGEN SENSOR