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Troubleshooting

DTC P0134 OXYGEN SENSOR CIRCUIT NO ACTIVITY DETECTED (BANK 1 SENSOR 1)

CIRCUIT DESCRIPTION

DTC Detecting Condition:




A thermistor built in the water temperature sensor changes the resistance value according to the water temperature.

The structure of the sensor and connection to the ECM is the same as the those of the air temperature sensor.

HINT:
- After confirming DTC P0134 and P0154, use the hand-held tester or OBD II scan tool to confirm voltage output of the A/F sensor (bank 1 sensor 1) from the CURRENT DATA.
- The ECM controls the voltage of the AF1A+ and AF1A- terminals of the ECM to the fixed voltage.
Therefore, it is impossible to confirm the A/F sensor output voltage without the hand-held tester or OBD II scan tool.
- OBD II scan tool (excluding hand-held tester) displays the one-fifth of the A/F sensor output voltage which is displayed on the hand-held tester.

Wiring Diagram:






Step 1 - 2:




Step 2 (continued):




Step 3 - 5:




Step 5 (continued) - 7:




Step 8 - 14:




Step 15 - 18:




INSPECTION PROCEDURE

HINT:
- Read freeze frame data using hand-held tester or OBD II scan tool, as 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.
- If the vehicle is short of fuel, the air-fuel ratio is LEAN and DTC P0134, P0154 will be recorded. The MIL then comes on.

CONFIRMATION DRIVING PATTERN




a. Switch the hand-held tester from the normal mode to the check mode. *1
b. Start the engine and idle the engine for 100 seconds or more. *2
c. Drive the vehicle at 40 km/h (24 mph) or more for 20 seconds or more. *3
d. Idle the engine for 20 seconds or more. *4
e. Repeat the steps (c) and (d) 3 times.
f. Idle the engine for 30 seconds. *5
g. Check the 02 sensor output voltage.

HINT: If a malfunction exists, the malfunction indicator light comes on.

NOTE: If the conditions on this test are not strictly followed, the malfunction will not be detected.

CHECK FOR INTERMITTENT PROBLEMS

Hand-held tester only:
By putting the vehicle's ECM in the check mode, the 1 trip detection logic is possible instead of the 2 trip detection logic and the sensitivity to detect open circuits is increased. This makes it easier to detect intermittent problems.

1. Clear the DTCs.
2. Set the check mode.
3. Perform a simulation test.
4. Check the connector and terminal.
5. Handle the connector.