DTC P2A01
DTC P2A01: Rear secondary Heated Oxygen Sensor (Secondary HO2S (Bank 1, Sensor 2)) Circuit Range/ Performance Problem
General Description
The rear secondary heated oxygen sensor (secondary HO2S (bank 1, sensor 2)) detects the oxygen density in the exhaust gas and converts it into electrical signals. If the rear secondary HO2S (bank 1, sensor 2) output voltage is a specified value for a set time, the powertrain control module (PCM) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 6 seconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Rear secondary HO2S (bank 1, sensor 2) output voltage [HO2S B1 S2] | - | 1.0 V |
| State of the engine | Running | |
[ ]: HDS Parameter
Malfunction Threshold
The rear secondary HO2S (bank 1, sensor 2) output voltage [HO2S B1 S2] is 1.54 V or less for at least 6 seconds after the rear secondary HO2S (bank 1, sensor 2) is judged that it is normally activated (1.0 V or less as a value).
Possible Cause
NOTE: 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) failure
- PCM internal circuit failure
Confirmation Procedure
Operating Condition
Start the engine. Hold the engine speed [ENGINE SPEED] at 3, 000 min -1 (rpm) without load (in P or N) until the radiator fan comes on.
With the HDS
None.
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 or by disconnecting the 12 volt battery.