Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Component Inspection
- INSPECTION START
Do you have CONSULT '
>>
GO TO 2.
>>
GO TO 3.
- CHECK HEATED OXYGEN SENSOR 2
With CONSULT
- Turn ignition switch ON.
- On CONSULT screen, select "ENGINE">>"Data Monitor".
- Start engine and warm it up to the normal operating temperature.
- Turn ignition switch OFF and wait at least 10 seconds.
- Start engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
- Let engine idle for 1 minute.
- On CONSULT screen, select "ENGINE">>"Active Test">>"FUEL INJECTION"
- Check "HO2S2 (B2)" at idle speed when adjusting "FUEL INJECTION" to ±25%.
"HO2S2 (B2)" should be above
0.72 V at least once when the "FUEL INJECTION" is +25%."HO2S2 (B2)" should be below
0.27 V at least once when the "FUEL INJECTION" is -25%.
Is the inspection result normal?
>>
INSPECTION END
>>
Replace malfunctioning heated oxygen sensor 2. Refer to Removal and Installation .
- CHECK HEATED OXYGEN SENSOR 2-I
Without CONSULT
- Start engine and warm it up to the normal operating temperature.
- Turn ignition switch OFF and wait at least 10 seconds.
- Start engine and keep the engine speed between 3, 500 and 4, 000 RPM for at least 1 minute under no load.
- Let engine idle for 1 minute.
- Check the voltage between ECM harness connector terminals under the following condition.
ECM Condition Voltage Connector + - Terminal F78 51 [HO2S2 (bank 2)] 81 Revving up to 4, 000 RPM under no load at least 10 times The voltage should be above 0.72 V at least once during this procedure. The voltage should be below 0.27 V at least once during this procedure.
Is the inspection result normal?
>>
INSPECTION END
>>
GO TO 4.
- CHECK HEATED OXYGEN SENSOR 2-II
Check the voltage between ECM harness connector terminals under the following condition.
ECM Condition Voltage Connector + - Terminal F78 51 [HO2S2 (bank 2)] 81 Keeping engine at idle for 10 minutes The voltage should be above 0.72 V at least once during this procedure. The voltage should be below 0.27 V at least once during this procedure. Is the inspection result normal?
>>
INSPECTION END
>>
GO TO 5.
- CHECK HEATED OXYGEN SENSOR 2-III
Check the voltage between ECM harness connector terminals under the following condition.
ECM Condition Voltage Connector + - Terminal F78 51 [HO2S2 (bank 2)] 81 Coasting from 80 km/h (50 MPH) in D position The voltage should be above 0.72 V at least once during this procedure. The voltage should be below 0.27 V at least once during this procedure. Is the inspection result normal?
>>
INSPECTION END
>>
Replace malfunctioning heated oxygen sensor 2. Refer to Removal and Installation .
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.