P0152

DTC P0152: Cylinder 2, 3 Heated Oxygen Sensor (front) Circuit High Voltage

Cylinder 2, 3 Heated Oxygen Sensor (front) Circuit Part 1:

Cylinder 2, 3 Heated Oxygen Sensor (front) Circuit Part 2:

CIRCUIT OPERATION
- A voltage corresponding to the oxygen concentration in the exhaust gas is sent to the PCM (terminal No. 91) from the output terminal (terminal No. 4) of the cylinder 2, 3 heated oxygen sensor (front).
- Terminal No. 2 of the cylinder 2, 3 heated oxygen sensor (front) is grounded with PCM (terminal No. 79).
- The PCM applies an offset voltage of 0.5 volt to terminal No. 2 of the cylinder 1, 4 heated oxygen sensor (front).

TECHNICAL DESCRIPTION
- A voltage corresponding to the oxygen concentration in the exhaust gas is sent to the PCM (terminal No. 91) from the output terminal (terminal No. 4) of the cylinder 2, 3 heated oxygen sensor (front).
- When the cylinder 2, 3 heated oxygen sensor (front) begins to deteriorate, the heated oxygen sensor signal response becomes poor.
- The PCM checks for the cylinder 2, 3 heated oxygen sensor (front) output voltage.

DESCRIPTIONS OF MONITOR METHODS
Cylinder 2, 3 heated oxygen sensor (front) output voltage is over specified range.

MONITOR EXECUTION
Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)
- Heated oxygen sensor heater (front) monitor
- Misfire monitor
- Fuel system monitor

Sensor (The sensor below is determined to be normal)
- Mass airflow sensor
- Engine coolant temperature sensor
- Intake air temperature sensor
- Barometric pressure sensor
- Throttle position sensor
- Accelerator pedal position sensor

DTC SET CONDITIONS

Logic Flow Chart:

Logic Flow Chart

Check Condition
- 2 seconds or more have passed since the engine starting sequence was completed.
- Heated oxygen sensor offset voltage is between 0.4 and 0.6 volt.

Judgement Criterion
- Cylinder 2, 3 heated oxygen sensor (front) output voltage has continued to be 1.8 volts or higher for 2 seconds.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 24. OBD-II Drive Cycle Pattern Lists

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Short circuit in cylinder 2, 3 heated oxygen sensor (front) output line.
- Connector damage.
- PCM failed.

DIAGNOSIS







STEP 1. Check harness connector B-36 at cylinder 2, 3 heated oxygen sensor (front) and harness connector B-22 at PCM for damage.
Q: Is the harness connector in good condition?

YES: Go to Step 2.

NO: Repair or replace it. Then go to Step 3.







STEP 2. Check for short circuit to power supply between cylinder 2, 3 heated oxygen sensor (front) connector B-36 (terminal No. 4) and PCM connector B-22 (terminal No. 91).

Q: Is the harness wire in good condition?

YES: Replace the PCM. When the PCM is replaced, register the encrypted code. Refer to Encrypted Code Registration Criteria Table in Antitheft and Alarm Systems. 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 Diagnostic Function - OBD-II Drive Cycle - Pattern 24. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P0152 set?

YES: Retry the troubleshooting.

NO: The inspection is complete.