Mazda 3 - Dtc P0031 [Z6]

Mazda 3 Workshop Manual – Engine + Wiring Diagrams + Diagnostic Trouble Codes
Downloaded from https://carmanualshub.com/ - automotive repair manuals website
50
DTC P0031 [Z6]
B3E010200001W03
DTC P0031
Front HO2S heater control circuit low
DETECTION
CONDITION
• The PCM monitors front HO2S heater control voltage at PCM terminal
2AM. If PCM turns front HO2S heater off but front HO2S heater circuit has
low voltage, PCM determines that front HO2S heater circuit has malfunction.
Note
• Front HO2S heater is controlled by duty signal.
Diagnostic support note
• This is a continuous monitor (HO2S heater).
• 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
• Front HO2S heater malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between front HO2S terminal C and PCM
terminal 2T
• Open circuit in wiring harness between front HO2S terminal D and PCM
terminal 2AM
• Short to ground in wiring harness between front HO2S terminal D and PCM
terminal 2AM
• PCM malfunction