FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

P0130

DTC P0130: Heated Oxygen Sensor Circuit

Heated Oxygen Sensor (front) Circuit Part 1:




Heated Oxygen Sensor (front) Circuit Part 2:






CIRCUIT OPERATION
- A voltage corresponding to the oxygen concentration in the exhaust gas is sent to the ECM (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.49).

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.
- When the heated oxygen sensor (front) begins to deteriorate, the heated oxygen sensor signal response becomes poor.
- The ECM 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 also checks for an open circuit in the heated oxygen sensor (front) output line.

DESCRIPTIONS OF MONITOR METHODS
- Heated oxygen sensor (front) circuit is switched to 5 volts intentionally when oxygen sensor output is low, and detects the malfunction if the output voltage changes to equal or greater than 4.5 volts. The above procedure is repeated when oxygen sensor is inactive.

MONITOR EXECUTION
- Continuous

MONITOR EXECUTION CONDITIONS (Other monitor and Sensor)

Other Monitor (There is no temporary DTC stored in memory for the item monitored below)
- Heated oxygen sensor heater (front) monitor
- Misfire monitor
- Fuel system monitor

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

DTC SET CONDITIONS

Logic Flow Chart:




Logic Flow Chart

Check Conditions
- 3 minutes or more have passed since the engine starting sequence was completed.
- Heated oxygen sensor (front) signal voltage has continued to be 0.2 volt or lower.
- Engine coolant temperature is higher than 76 degrees C (169 degrees F).
- Engine speed is higher than 1,200 r/min.
- Volumetric efficiency is higher than 25 percent.
- Monitoring time: 7 seconds.

Judgment Criterion
- Input voltage supplied to the ECM interface circuit is higher than 4.5 volts when 5 volts is applied to the heated oxygen sensor (front) output line via a resistor.

OBD-II DRIVE CYCLE PATTERN
Refer to Diagnostic Function - OBD-II Drive Cycle - Pattern 11. OBD-II Drive Cycle Pattern Lists

TROUBLESHOOTING HINTS (The most likely causes for this code to be set are:)
- Heated oxygen sensor (front) deteriorated.
- Open or shorted circuit in heated oxygen sensor (front) output line or harness damage.
- Open circuit in heated oxygen sensor (front) ground line or harness damage.
- ECM failed.

DIAGNOSIS

Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: V.C.I.
- MB991827: USB Cable
- MB991911: Main Harness B
- MD998464: Test Harness

STEP 1. Using scan tool MB991958, check data list item 11: Heated Oxygen Sensor (front).

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958 to the data link connector.
2. Start the engine and run at idle.
3. Set scan tool MB991958 to the data reading mode for item 11, Heated Oxygen Sensor (front).
- Warm up the engine. When the engine is revved, the output voltage should be 0.6 to 1.0 volt.
- Warm up the engine. When the engine is idling, the output voltage should repeat 0.4 volt and 0.6 to 1.0 volt alternately.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?

YES: It can be assumed that this malfunction is intermittent.

NO: Go to Step 2.

STEP 2. Measure the sensor output voltage at heated oxygen sensor (front) connector B-113 by backprobing.




1. Do not disconnect connector B-113.
2. Start the engine and run at idle.




3. Measure the voltage between terminal No.4 and ground by backprobing.
- Warm up the engine. When the engine is 2,500 r/min, the output voltage should repeat 0 to 0.8 volt alternately.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage within the specified range?

YES: Go to Step 3.

NO: Go to Step 7.

STEP 3. Measure the sensor output voltage at ECM connector C-117 by backprobing.




1. Do not disconnect connector C-117.
2. Start the engine and run at idle.




3. Measure the voltage between terminal No.71 and ground by backprobing.
- Warm up the engine. When the engine is 2,500 r/min, the output voltage should repeat 0 to 0.8 volt alternately.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the measured voltage within the specified range?

YES: Go to Step 4.

NO: Go to Step 6.







STEP 4. Check harness connector B-113 at heated oxygen sensor (front) and connector C-117 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 5.

NO: Repair or replace it. Then go to Step 15.

STEP 5. Using scan tool MB991958, check data list item 11: Heated Oxygen Sensor (front).

CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.




1. Connect scan tool MB991958 to the data link connector.
2. Start the engine and run at idle.
3. Set scan tool MB991958 to the data reading mode for item 11, Heated Oxygen Sensor (front).
- Warm up the engine. When the engine is revved, the output voltage should be 0.6 to 1.0 volt.
- Warm up the engine. When the engine is idling, the output voltage should repeat 0.4 volt and 0.6 to 1.0 volt alternately.

4. Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the sensor operating properly?

YES: It can be assumed that this malfunction is intermittent.

NO: Replace the ECM. Then go to Step 15.







STEP 6. Check harness connector B-113 at heated oxygen sensor (front) and connector C-117 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Repair harness wire between heated oxygen sensor (front) connector B-113 (terminal No.4) and ECM connector C-117 (terminal No.71) because of open circuit or harness damage. Then go to Step 15.

NO: Repair or replace it. Then go to Step 15.




STEP 7. Check harness connector B-113 at heated oxygen sensor (front) for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 8.

NO: Repair or replace it. Then go to Step 15.

STEP 8. Check for continuity at heated oxygen sensor (front) harness side connector B-113.




1. Disconnect connector B-113 and measure at the harness side.




2. Check for the continuity between terminal No.2 and ground.
- Should be less than 2 Ohms.

Q: Does continuity exist?

YES: Go to Step 11.

NO: Go to Step 9.




STEP 9. Check harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 10.

NO: Repair or replace it. Then go to Step 15.







STEP 10. Check for open circuit and harness damage between heated oxygen sensor (front) connector B-113 (terminal No.2) and ECM connector C-119 (terminal No. 49).

Q: Is the harness wire in good condition?

YES: Replace the ECM. Then go to Step 15.

NO: Repair it. Then go to Step 15.




STEP 11. Check harness connector C-119 at ECM for damage.

Q: Is the harness connector in good condition?

YES: Go to Step 12.

NO: Repair or replace it. Then go to Step 15.







STEP 12. Check for harness damage between heated oxygen sensor (front) connector B-113 (terminal No.2) and ECM connector C-119 (terminal No.49).

Q: Is the harness wire in good condition?

YES: Go to Step 13.

NO: Repair it. Then go to Step 15.







STEP 13. Check for short circuit to ground and harness damage between heated oxygen sensor (front) connector B-113 (terminal No.4) and ECM connector C-117 (terminal No.71).

Q: Is the harness wire in good condition?

YES: Go to Step 14.

NO: Repair it. Then go to Step 15.

STEP 14. Check the heated oxygen sensor (front).




1. Disconnect the heated oxygen sensor (front) connector B-113 and connect test harness special tool, MD998464, to the connector on the heated oxygen sensor (front) side.
2. Warm up the engine until engine coolant temperature reaches 80 degrees C (176 degrees F) or higher.




3. Perform a racing for 5 minutes or more with the engine speed of 4,500 r/min.
4. Connect a digital voltage meter between terminal No.2 (black clip) and terminal No.4 (white clip).
5. While repeatedly revving the engine, measure the heated oxygen sensor (front) output voltage.

Standard value: 0.6 - 1.0 volt

CAUTION:
- Be very careful when connecting the jumper wires; incorrect connection can damage the heated oxygen sensor.
- Be careful the heater is broken when voltage of beyond 8 volts is applied to the heated oxygen sensor heater.

NOTE: If the sufficiently high temperature [of approximate 400 degrees C (752 degrees F) or more] is not reached although the heated oxygen sensor is normal, the output voltage would be possibly low although the rich air/fuel ratio. Therefore, if the output voltage is low, use a jumper wire to connect the terminal No.1 (red clip) and the terminal No.3 (blue clip) of the heated oxygen sensor with the positive terminal and the negative terminal of 8 volts power supply respectively, then check again.

Q: Is the measured voltage between 0.6 and 1.0 volt?

YES: Replace the ECM. Then go to Step 15.

NO: Replace the heated oxygen sensor (front). Then go to Step 15.

STEP 15. 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 11. OBD-II Drive Cycle Pattern Lists
2. Check the diagnostic trouble code (DTC).

Q: Is DTC P0130 set?

YES: Retry the troubleshooting.

NO: The inspection is complete.