Except California Emission Regulation Applicable ATX Model
DTC P0139 DETECTION CONDITION AND POSSIBLE CAUSES
| DTC P0139 |
Rear HO2S circuit problem |
| DETECTION CONDITION |
- The PCM monitors the rich (0.4 V
) to lean (0.3 V
) response time of the rear HO2S. The PCM measure the response time when the following conditions are met. The PCM determines the rear HO2S response deterioration malfunction when the measured response time is more than the threshold value (80 ms
) five consecutive times.
MONITORING CONDITIONS
- HO2S heater, HO2S, and TWC Repair Verification Drive Mode or EGR, HO2S heater, HO2S, TWC, and EVAP System Repair Verification Drive Mode
- Following conditions are met:
- Fuel cut during deceleration
- Engine speed is above 500 RPM.
- Engine coolant temperature is above 70 °C {158 °F}.
- HO2S (rear) output voltage is above 0.4 V.
- The PCM monitors for a time-out malfunction (when rear HO2S remains above 0.3 V for longer than a specified period of time during fuel cut control). The PCM measure the amount of time from when the following conditions are met until the rear HO2S output voltage drops below 0.3 V.
The PCM determines a HO2S time-out malfunction when the detected time is more than the threshold value (6 s
) three consecutive times.
MONITORING CONDITIONS
- HO2S heater, HO2S, and TWC Repair Verification Drive Mode or EGR, HO2S heater, HO2S, TWC, and EVAP System Repair Verification Drive Mode
- Following conditions are met:
- Fuel cut during deceleration
- Engine speed is above 500 RPM.
- Engine coolant temperature is above 70 °C {158 °F}.
- HO2S (rear) is activated (more than 0.55 V
).
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.
- DIAGNOSTIC MONITORING TEST RESULTS is available.
- PENDING CODE is available if the PCM detects the above malfunction condition during first drive cycle.
- FREEZE FRAME DATA is available.
- DTC is stored in the PCM memory.
|
| POSSIBLE CAUSE |
- Rear HO2S deterioration
- Rear HO2S malfunction
- Looseness rear HO2S
- Pressure regulator (built-in fuel pump unit) malfunction
- Fuel pump malfunction
- Fuel filter (built-in fuel pump unit) clogged or restricted
- Fuel leakage on fuel line from fuel distribution pipe and fuel pump
- Leakage exhaust system
- Purge solenoid valve malfunction
- Purge solenoid hoses improper connection
- Insufficient compression
- Engine malfunction (Leakage engine coolant)
|