DTC Advanced Diagnostics: P0141 (3.5L Engine)
DTC P0141: Rear Secondary Heated Oxygen Sensor (Secondary HO2S (Bank 1, Sensor 2)) Heater Circuit Malfunction
General Description
A heater for the zirconia element is embedded in the rear secondary heated oxygen sensor (secondary HO2S (bank 1, sensor 2)), and it is controlled by the powertrain control module (PCM). When activated, it heats the sensor to stabilize and speed up the detection of oxygen content when the exhaust gas temperature is cold. If the rear secondary HO2S (bank 1, sensor 2) heater draws other than a specified amperage, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 5.0 seconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [Battery] (IGP terminal of PCM) | 10.5 V | - |
| State of the engine | Running | |
[ ]: HDS Parameter
Malfunction Threshold
The rear secondary HO2S (bank 1, sensor 2) heater output is 0.38 A or less, or 3.33 A or more, for at least 5.0 seconds when the heater is on.
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Rear secondary HO2S (bank 1, sensor 2) heater failure
- Rear secondary HO2S (bank 1, sensor 2) SO2HT_B1 line open
- Rear secondary HO2S (bank 1, sensor 2) SO2HT_B1 line short to ground
- Rear secondary HO2S (bank 1, sensor 2) heater power supply line open (includes fuse blown)
- Rear secondary HO2S (bank 1, sensor 2) heater internal circuit open
- Poor ignition switch
- PCM internal circuit failure
Confirmation Procedure
Operating Condition
Start the engine, and let it idle until the radiator fan comes on.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.