P0141
P0141-O2 SENSOR 1/2 HEATER PERFORMANCE
Special Tools:
For a complete wiring diagram, refer to the Wiring Information.
- When Monitored:
With the engine running, O2 sensor heater duty cycle greater than 0% and battery voltage greater than 11.0 volts.
- Set Condition:
The PCM detects no O2 sensor output when the heater is powered up. Two trip fault. Three good trips to turn off the MIL.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. PCM Pre-Diagnostic Troubleshooting Procedure.
Diagnostic Test
1. OXYGEN SENSOR 1/2 HEATER CONTROL OPERATION
1. Turn the ignition off.
NOTE: Wait A Minimum Of 8 minutes to allow the sensor to cool down before continuing. The sensor voltage should stabilize between 2.47 and 2.52 volts.
2. Turn the ignition on.
3. With a scan tool, actuate the Oxygen Sensor 1/1 heater control.
4. With the scan tool, monitor 1/1 O2 Sensor Volts for at least two minutes.
Does the voltage stay between 2.47 and 2.52 volts?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. PCM Intermittent Condition Test.
2. OXYGEN SENSOR 1/2
1. Turn the ignition off.
NOTE: Wait a minimum of eight minutes to allow the sensor to cool down before continuing.
2. Disconnect the Oxygen Sensor 1/2 harness connector.
3. Measure the resistance of the O2 sensor heater element across the Oxygen Sensor 1/2 connector between the heater control terminal and the ground terminal.
NOTE: The O2 heater element resistance should be measured at 21.1°C (70°F). The resistance value will vary at different temperatures.
Is the resistance between 2.0 and 30.0 Ohms?
Yes
- Go To 3
No
- Replace the Oxygen Sensor 1/2. Oxygen Sensor - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
3. CHECK THE (K299) O2 1/2 HEATER CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Disconnect the PCM harness connector.
CAUTION:
Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
2. Connect the (10436).
3. Measure the resistance of the (K299) O2 1/2 Heater Control circuit from the Oxygen Sensor 1/2 harness connector to the GPEC Adaptor.
Is the resistance below 0.5 Ohms?
Yes
- Go To 4
No
- Repair the (K299) O2 1/2 Heater Control circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
4. CHECK THE GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Using a 12 volt test light connected to 12 volts, check the Ground circuit in the Oxygen Sensor 1/2 harness connector.
NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.
Is the test light illuminated and bright?
Yes
- Go To 5
No
- Repair the Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
5. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 1/2 and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins (TSBs) that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.
No
- Replace and program the Powertrain Control Module (PCM). Powertrain Control Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.