FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0152

Left Bank Heated Oxygen Sensor (front) Circuit:




Connectors:





CIRCUIT OPERATION
- A voltage corresponding to the oxygen concentration in the exhaust gas is sent to the ECM (terminal No.71) or PCM (terminal No.71) from the output terminal (terminal No.4) of the left bank heated oxygen sensor (front).
- Terminal No.2 of the left bank heated oxygen sensor (front) is grounded with ECM (terminal No.49) or PCM (terminal No.57)
.

TECHNICAL DESCRIPTION
- The left bank heated oxygen sensor (front) detects the concentration of oxygen in the exhaust gas; it converts that data to voltage, and sends it to the ECM or PCM
.
- When the left bank heated oxygen sensor (front) begins to deteriorate, the heated oxygen sensor signal response deteriorates also.
- The ECM or PCM
varies the air/fuel mixture to make it leaner and richer, and checks the response speed of the left bank heated oxygen sensor (front). In addition, the ECM or PCM also checks for an open circuit in the left bank heated oxygen sensor (front) output line.

DTC SET CONDITIONS

Check Conditions
- 2 seconds or more have passed since the starting sequence was completed.

Judgment Criteria
- Left bank heated oxygen sensor (front) output voltage has continued to be 1.2 volts or higher for 2 seconds.

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Short circuit in left bank heated oxygen sensor (front) output line.
- ECM failed.
- PCM failed.


DIAGNOSIS

Required Special Tool:
- MB991502: Scan Tool (MUT-II)

Connectors:





STEP 1. Check connector B-24 at left bank heated oxygen sensor (front) and connector C-122 at ECM or connector C-119 at PCM
for damage.

Q: Is the connector in good condition?

YES: Go to Step 2.
NO: Repair or replace it. Refer to Harness Connector Inspection. Then go to Step 3.

Connectors:





STEP 2. Check for short circuit to power supply between left bank heated oxygen sensor (front) connector B-24 (terminal No.4) and ECM connector C-122 (terminal No.71) or PCM connector C-119 (terminal No.71)
.

Q: Is the harness wire in good condition?

YES: Replace the ECM or PCM. Then go to Step 3.
NO: Repair it. Then go to Step 3.

STEP 3. Test the OBD-II drive cycle.

1. Carry out a test drive with the drive cycle pattern. Refer to Trouble Code Diagnosis - OBD-II Drive Cycle - Procedure 6 - Other Monitor.
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P0152 set?

YES: Retry the troubleshooting.
NO: The inspection is complete.