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DTC P0131-00; A/F Sensor Circuit Low Input: Notes

NOTE:

To determine the malfunctioning part, proceed with the diagnostics from "Function Inspection Using M-MDS".

Details On DTCs

DETECTION CONDITION AND POSSIBLE CAUSE

DESCRIPTION	A/F sensor circuit low input
DETECTION CONDITION	Determination conditions	Any one of the following conditions is met: Voltage of A/F sensor terminal F is less than specified value Voltage of A/F sensor terminal D is less than specified value Voltage of A/F sensor terminal B is less than specified value
	Preconditions	Switch the ignition ON (engine off or on) Battery voltage: 11-18 V^1 The following DTC is not detected: Internal PCM malfunction: P064D:00 ^1 : Value can be verified by displaying PIDs using M-MDS
	Drive cycle	2
	Self test type	CMDTC self test, KOER self test
	Sensor used	A/F sensor
FAIL-SAFE FUNCTION	Fixes duty value of A/F sensor heater Stops fuel feedback control of A/F sensor
VEHICLE STATUS WHEN DTCs ARE OUTPUT	Illuminates check engine light.
POSSIBLE CAUSE	A/F sensor connector or terminals malfunction PCM connector or terminals malfunction Short to ground in wiring harness between the following terminals: A/F sensor terminal F-PCM terminal 1G A/F sensor terminal D-PCM terminal 1C A/F sensor terminal B-PCM terminal 1L A/F sensor malfunction PCM malfunction