Diesel Data: Automotive Repair

P0132

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.76) or PCM (terminal No.71) from the output terminal (terminal No.4) of the heated oxygen sensor (front).
- Terminal No.2 of the heated oxygen sensor (front) is grounded with ECM (terminal No.92) or PCM (terminal No.57)
.

TECHNICAL DESCRIPTION
- The heated oxygen sensor (front) detects the concentration of oxygen in the exhaust gas; it converts those data to voltage, and inputs the resulting signals to the ECM or PCM
.
- When the heated oxygen sensor (front) begins to deteriorate, the heated oxygen sensor signal response becomes poor.
- The ECM or PCM
forcibly varies the air/fuel mixture to make it leaner and richer and checks the response speed of the heated oxygen sensor (front). In addition, the ECM or PCM also checks for an open circuit in the 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
- 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:)
- Heated oxygen sensor (front) deteriorated.
- Short circuit in 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-11 at heated oxygen sensor (front) and connector C-120 at ECM or connector C-114 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 heated oxygen sensor (front) connector B-17 (terminal No. 4) and ECM connector C-120 (terminal No.76) or PCM connector C-117 (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 P0132 set?

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