DTC P0131:00 [MZI-3.7]: Notes

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DETECTION CONDITION & POSSIBLE CAUSE

DTC P0131:00	A/F sensor circuit low input
DETECTION CONDITION	If the voltage for control of the A/F sensor in the PCM is 1.13 V (+ terminal) or lower, or 0.64 V (- terminal) or lower. Diagnostic support note This is an intermittent monitor (A/F sensor, 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. The DTC is stored in the PCM memory if the PCM detects the above malfunction condition.
POSSIBLE CAUSE	A/F sensor malfunction Connector or terminal malfunction Open circuit in wiring harness between A/F sensor (LH) terminal 3 and PCM terminal 2AK Short to ground in wiring harness between A/F sensor (LH) terminal 3 and PCM terminal 2AK Open circuit in wiring harness between A/F sensor (RH) terminal 3 and PCM terminal 2AG Short to ground in wiring harness between A/F sensor (RH) terminal 3 and PCM terminal 2AG Open circuit in wiring harness between A/F sensor (LH) terminal 5 and PCM terminal 2AE Short to ground in wiring harness between A/F sensor (LH) terminal 5 and PCM terminal 2AE Open circuit in wiring harness between A/F sensor (RH) terminal 5 and PCM terminal 2AC Short to ground in wiring harness between A/F sensor (RH) terminal 5 and PCM terminal 2AC PCM malfunction
Courtesy of MAZDA MOTORS CORP.

DTC P0131:00

A/F sensor circuit low input

DETECTION CONDITION

If the voltage for control of the A/F sensor in the PCM is 1.13 V (+ terminal) or lower, or 0.64 V (- terminal) or lower.

Diagnostic support note

This is an intermittent monitor (A/F sensor, 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.
The DTC is stored in the PCM memory if the PCM detects the above malfunction condition.

POSSIBLE CAUSE

A/F sensor malfunction
Connector or terminal malfunction
Open circuit in wiring harness between A/F sensor (LH) terminal 3 and PCM terminal 2AK
Short to ground in wiring harness between A/F sensor (LH) terminal 3 and PCM terminal 2AK
Open circuit in wiring harness between A/F sensor (RH) terminal 3 and PCM terminal 2AG
Short to ground in wiring harness between A/F sensor (RH) terminal 3 and PCM terminal 2AG
Open circuit in wiring harness between A/F sensor (LH) terminal 5 and PCM terminal 2AE
Short to ground in wiring harness between A/F sensor (LH) terminal 5 and PCM terminal 2AE
Open circuit in wiring harness between A/F sensor (RH) terminal 5 and PCM terminal 2AC
Short to ground in wiring harness between A/F sensor (RH) terminal 5 and PCM terminal 2AC
PCM malfunction

Courtesy of MAZDA MOTORS CORP.