DTC P0131:00 [MZR 1.6]

id0102h3702200

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 check engine light 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 (Mode 2)/Snapshot data is available.
•  DTC is stored in the PCM memory.
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 A—PCM terminal 2AQ
―  A/F sensor terminal B—PCM terminal 2AV
•  A/F sensor malfunction
•  PCM malfunction

Diagnostic Procedure

STEP

INSPECTION

ACTION
1
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA (MODE 2)
•  Perform the Freeze Frame PID Data Access Procedure.
•  Is the DTC P0131:00 on FREEZE FRAME DATA (Mode 2)?
Yes
Go to the next step.
No
Go to the troubleshooting procedures for DTC on FREEZE FRAME DATA (Mode 2).
(See DTC TABLE [MZR 1.6].)
2
VERIFY FREEZE FRAME DATA (MODE 2)/SNAPSHOT DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED
•  Have the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS (A/F sensor, HO2S related) been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA (Mode 2)/snapshot data and DIAGNOSTIC MONITORING TEST RESULTS on repair order, then go to the next step.
3
VERIFY RELATED SERVICE INFORMATION AVAILABILITY
•  Verify related Service Information availability.
•  Is any related Service Information available?
Yes
Perform repair or diagnosis according to the available Service Information.
•  If the vehicle is not repaired, go to the next step.
No
Go to the next step.
4
VERIFY RELATED PENDING CODE AND STORED DTC
•  Switch the ignition off, then ON (engine off).
•  Verify the related PENDING CODE and stored DTCs using the M-MDS.
•  Are any other DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR 1.6].)
No
Go to the next step.
5
INSPECT A/F SENSOR CONNECTOR CONDITION
•  Switch the ignition off.
•  Disconnect the A/F sensor connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
6
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
•  Is there any malfunction?
Yes
Repair or replace the connector or terminals, then go to Step 9.
No
Go to the next step.
7
INSPECT A/F SENSOR CIRCUIT FOR SHORT TO GROUND
•  Verify that the A/F sensor and PCM connectors are disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side) and body ground:
―  A/F sensor terminal A
―  A/F sensor terminal B
•  Is there continuity?
Yes
Refer to the wiring diagram and verify whether or not there is a common connector between the following terminals:
•  A/F sensor terminal A—PCM terminal 2AQ
•  A/F sensor terminal B—PCM terminal 2AV
If there is a common connector:
•  Determine the malfunctioning part by inspecting the common connector and the terminal for corrosion, damage, or pin disconnection, and the common wiring harness for a short to ground.
•  Repair or replace the malfunctioning part.
If there is no common connector:
•  Repair or replace the wiring harness which has a short to ground.
Go to Step 9.
No
Go to the next step.
8
INSPECT A/F SENSOR
•  Reconnect all disconnected connectors.
•  Inspect the A/F sensor.
•  Is there any malfunction?
Yes
Replace the A/F sensor, then go to the next step.
(See AIR FUEL RATIO (A/F) SENSOR REMOVAL/INSTALLATION [MZR 1.6].)
No
Go to the next step.
9
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Always reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Perform the KOER self test.
•  Is the PENDING CODE for this DTC present?
Yes
Repeat the inspection from Step 1.
•  If the malfunction recurs, replace the PCM.
Go to the next step.
No
Go to the next step.
10
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Are any DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR 1.6].)
No
DTC troubleshooting completed.