DTC P0139: Notes
DTC P0139 DETECTION & CONDITION POSSIBLE CAUSES
| DTC P0139 |
Rear HO2S circuit slow response |
| DETECTION CONDITION |
- The PCM monitors the rear HO2S inversion cycle period and rich-to-lean response time while under the open loop fuel control (fuel cut off control). If the average response time is more than the specification, the PCM determines that the rear HO2S circuit response is slow.
Diagnostic support note
- This is an intermittent monitor (HO2S).
- The MIL illuminates if the PCM detects the above malfunction condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
- PENDING CODE is available if the PCM detects the above malfunction condition during the first drive cycle.
- FREEZE FRAME DATA is available.
- The DTC is stored in the PCM memory.
|
| POSSIBLE CAUSE |
- Purge solenoid valve malfunction
- Looseness of rear HO2S
- Leakage exhaust gas
- Rear HO2S malfunction
- Fuel line pressure malfunction
- Leakage fuel
- Fuel pump unit malfunction
- AIR system malfunction
- Leakage engine coolant
- PCM malfunction
|