Dtc P0140 - Mazda 6 2002 Workshop Manual

STEP
7 VERIFY TROUBLESHOOTING OF DTC P0138
COMPLETED
• Make sure to reconnect all disconnected
connectors.
• Turn ignition key to ON (Engine OFF).
• Clear DTC from memory using WDS or
equivalent.
• Run PCM adaptive memory procedure drive
mode and HO2S heater, HO2S, and TWC
repair verification drive mode.
(See F–64 OBD DRIVE
• Is PENDING CODE the same as DTC
present?
8 VERIFY AFTER REPAIR PROCEDURE
• Perform “After Repair Procedure”.
(See F–66 AFTER REPAIR
• Is there any DTC present?
End Of Sie

DTC P0140

DTC P0140 Rear HO2S circuit no activity detected
• PCM monitors input voltage from rear HO2S when the following conditions are met. If input voltage from
sensor never eceed 0.55 V for 30.4 s, PCM determines that sensor circuit is not activated.
MONITORING CONDITIONS
— HO2S, HO2S heater and TWC repair verification drive mode
— Following conditions are met:
• Engine speed is above 1,500 rpm.
DETECTION • Engine coolant temperature is above 80 ° ° ° ° C {158 ° ° ° ° F}.
CONDITION Diagnostic support note
• This is a continuous monitor (CCM).
• MIL illuminates if 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 PCM detects the above malfunction condition during first drive cycle.
• FREEZE FRAME DATA is available.
• DTC is stored in the PCM memory.
• Rear HO2S deterioration
• Rear HO2S heater malfunction
POSSIBLE • Leakage ehaust system
CAUSE • Open or short to ground circuit between rear HO2S terminal A and PCM terminal 1Y
• Insufficient compression
• Engine malfunction
F–114
ON-BOARD DIAGNOSTIC
INSPECTION
MODE.)
PROCEDURE.)
Yes Replace PCM, then go to net step.
(See F–43 PCM REMOVAL/INSTALLATION.)
No Go to net step.
Yes Go to applicable DTC troubleshooting.
(See F–67 DTC TABLE.)
No Troubleshooting completed.
ACTION
A6E397001084W26