Except California Emission Regulation Applicable ATX Model

DTC P0131 DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0131	Front HO2S circuit low input
DETECTION CONDITION	The PCM monitors the input voltage from the front HO2S while the engine is running. If the input voltage is above 1.0 V  for 2 s  , the PCM determines that the front HO2S circuit voltage is low. Diagnostic support note  This is a continuous 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. Are any DTCs is stored in the PCM memory.
POSSIBLE CAUSE	Front HO2S malfunction Connector or terminal malfunction Open circuit in wiring harness between front HO2S terminal 1C and PCM terminal 2Z Short to ground in wiring harness between front HO2S terminal 1C and PCM terminal 2Z Open circuit in wiring harness between front HO2S terminal 1B and PCM terminal 2AC Short to ground in wiring harness between front HO2S terminal 1B and PCM terminal 2AC Open circuit in wiring harness between front HO2S terminal 1A and PCM terminal 2AD Short to ground in wiring harness between front HO2S terminal 1A and PCM terminal 2AD PCM malfunction
Courtesy of MAZDA MOTORS CORP.