Code No. P0136: Right Bank Oxygen Sensor (Rear) Circuit

M11310100347ENG0000010000

OPERATION

The sensor signal is inputted to the engine-A/T-ECU (terminal No. 117) from the right bank oxygen sensor (rear) output terminal (terminal No. 4).
The right bank oxygen sensor (rear) (terminal No. 2) is earthed with engine-A/T-ECU (terminal No. 96).

FUNCTION

The right bank oxygen sensor (rear) converts the concentration of oxygen in the exhaust emission into a voltage and inputs the signal to the engine-A/T-ECU.
When the air-fuel ratio is richer than the theoretical air-fuel ratio, the right bank oxygen sensor (rear) outputs a voltage of about 1 V. When it is leaner than the theoretical air-fuel ratio, it outputs a voltage of about 0 V.
In response to the signal, the engine-A/T-ECU controls the fuel injection amount so that the air-fuel ratio can be equivalent to the theoretical air-fuel ratio.

TROUBLE JUDGMENT

Check Conditions

Above 3 minutes later after the engine has started up.
Right bank oxygen sensor (rear) output voltage is 0.15 V or less.
The engine coolant temperature is approximately 76°C or more.
The engine speed is 1,200 r/min or more.
Volumetric efficiency is 25% or more.
The monitoring time is 7 seconds.

Judgment Criterion

When a power voltage of 5 V is applied to the right bank oxygen sensor (rear) in the engine-A/T-ECU, the sensor output voltage is 4.5 V or more.

PROBABLE CAUSES

Failed right bank oxygen sensor (rear)
Open/short circuit in right bank oxygen sensor (rear) circuit or loose connector contact
Failed engine-A/T-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

Refer to Data List Reference Table .

Item AD: Right bank oxygen sensor (rear)

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Go to Step 2 .

STEP 2. Connector check: C-04 right bank oxygen sensor (rear) connector

Q. Is the check result normal?

Go to Step 3 .

Repair or replace the connector.

STEP 3. Perform resistance measurement at C-04 right bank oxygen sensor (rear) connector.

Disconnect connector, and measure at harness side.
Resistance between terminal No. 2 and earth.

OK: Continuity (2 Ω or less)

Q. Is the check result normal?

Go to Step 7 .

Go to Step 4 .

STEP 4. Connector check: D-217 engine-A/T-ECU connector

Q. Is the check result normal?

Go to Step 5 .

Repair or replace the connector.

STEP 5. Check harness between C-04 (terminal No. 2) right bank oxygen sensor (rear) connector and D-217 (terminal No. 96) engine-A/T-ECU connector.

note

Before checking harness, check intermediate connectors D-111 and D-225, and repair if necessary.

Check earthing line damage.

Q. Is the check result normal?

Go to Step 6 .

Repair the damaged harness wire.

STEP 6. M.U.T.-III data list

Refer to Data List Reference Table .

Item AD: Right bank oxygen sensor (rear)

Q. Is the check result normal?

	Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

	Replace engine-A/T-ECU.

STEP 7. Perform voltage measurement at C-04 right bank oxygen sensor (rear) connector.

Use special tool test harness (MB991316) to connect connector, and measure at pick-up harness.
Engine: After warm-up
Transmission: P range
Voltage between terminal No. 4 and earth.

OK:
When the engine is 2,500 r/min, the output voltage should repeat 0 to 0.8 V alternately.

Q. Is the check result normal?

Go to Step 10 .

Go to Step 8 .

STEP 8. Check right bank oxygen sensor (rear) itself.

Check right bank oxygen sensor (rear) itself (Refer to ).

Q. Is the check result normal?

	Go to Step 9 .

	Replace right bank oxygen sensor (rear).

STEP 9. Connector check: D-217 engine-A/T-ECU connector

Q. Is the check result normal?

Check output line for short circuit.

Repair or replace the connector.

STEP 10. Perform voltage measurement at D-217 engine-A/T-ECU connector.

Measure engine-A/T-ECU terminal voltage.
Transmission: P range
Engine: After warm-up
Voltage between terminal No. 117 and earth.

OK:
When the engine is 2,500 r/min, the output voltage should repeat 0 to 0.8 V alternately.

Q. Is the check result normal?

Go to Step 12 .

Go to Step 11 .

STEP 11. Connector check: D-217 engine-A/T-ECU connector

Q. Is the check result normal?

Check output line for open circuit.

Repair or replace the connector.

STEP 12. Connector check: D-217 engine-A/T-ECU connector

Q. Is the check result normal?

Repair or replace the connector.