DTC P0131 [L3]: Notes

DTC P0131 [L3] DETECTION CONDITIONS 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 any front HO2S terminal voltage is below 1.2 V for 1 s , the PCM determines that the front HO2S circuit voltage is low. MONITORING CONDITION Battery voltage: 10-18 V Diagnostic support note This is an continuous monitor (HO2S). 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 malfunction Connector or terminal malfunction Open circuit in wiring harness between front HO2S terminal F and PCM terminal 2Z Short to ground in wiring harness between front HO2S terminal F and PCM terminal 2Z Open circuit in wiring harness between front HO2S terminal D and PCM terminal 2AC Short to ground in wiring harness between front HO2S terminal D and PCM terminal 2AC Open circuit in wiring harness between front HO2S terminal B and PCM terminal 2AD Short to ground in wiring harness between front HO2S terminal B and PCM terminal 2AD PCM malfunction

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 any front HO2S terminal voltage is below 1.2 V for 1 s , the PCM determines that the front HO2S circuit voltage is low.

MONITORING CONDITION

Diagnostic support note

This is an continuous monitor (HO2S).
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 malfunction Connector or terminal malfunction
Open circuit in wiring harness between front HO2S terminal F and PCM terminal 2Z
Short to ground in wiring harness between front HO2S terminal F and PCM terminal 2Z
Open circuit in wiring harness between front HO2S terminal D and PCM terminal 2AC
Short to ground in wiring harness between front HO2S terminal D and PCM terminal 2AC
Open circuit in wiring harness between front HO2S terminal B and PCM terminal 2AD
Short to ground in wiring harness between front HO2S terminal B and PCM terminal 2AD
PCM malfunction