DTC Advanced Diagnostics: P0052 (3.0L Engine)
DTC P0052: Front Air/Fuel Ratio (A/F) Sensor (Bank 2, Sensor 1) Heater Circuit High Voltage
General Description
The front air/fuel ratio (A/F) sensor (bank 2, sensor 1) heater is controlled by the duty signal command from the powertrain control module (PCM) to heat the front A/F sensor (bank 2, sensor 1) to an optimal temperature. The monitor circuit in the PCM monitors the voltage level of the AFHTB2 terminal, and if an abnormality of the terminal voltage is detected, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 5 seconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| 12 volt battery voltage [Battery] | 10.0 V | - |
| Front A/F sensor (bank 2, sensor 1) heater output duty | 0.1 % | - |
| State of the engine | Running | |
[ ]: HDS Parameter
Malfunction Threshold
The monitor circuit in the PCM cannot detect the pulse edge of the front A/F sensor (bank 2, sensor 1) and the output terminal level shows high for at least 5 seconds while the front A/F sensor (bank 2, sensor 1) heater is duty controlled at 0.1 % or more.
Possible Cause
- Front A/F sensor (bank 2, sensor 1) AFHTB2 line short to power
- PCM internal circuit failure
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.