DTC P0131:00 [MZR 2.0, MZR 2.5]

id0102g3702200

DTC P0131:00

A/F sensor circuit low input
DETECTION CONDITION
•  The PCM monitors the input voltage from the A/F sensor while the engine is running. If the following PCM terminal voltage is below specified, the PCM determines that the A/F sensor circuit voltage is low.
―  PCM terminal 2Z: 1.2 V
―  PCM terminal 2AC: 1.2 V
―  PCM terminal 2AD: 2 V
Diagnostic support note
•  This is a continuous 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 (Mode 2)/Snapshot data is available.
•  The DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  A/F sensor connector or terminals malfunction
•  Short to ground in wiring harness between the following terminals:
―  A/F sensor terminal B—PCM terminal 2AD
―  A/F sensor terminal D—PCM terminal 2AC
―  A/F sensor terminal F—PCM terminal 2Z
•  PCM connector or terminals malfunction
•  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 2.0, MZR 2.5].)
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 to off, then to ON (engine off).
•  Perform the DTC Reading Procedure and Pending Trouble Code Access Procedure.
•  Are any other DTCs present?
Yes
Go to the applicable DTC inspection.
(See DTC TABLE [MZR 2.0, MZR 2.5].)
No
Go to the next step.
5
INSPECT A/F SENSOR CONNECTOR CONDITION
•  Switch the ignition to off.
•  Disconnect the A/F sensor connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal and/or connector, then go to Step 9.
No
Go to the next step.
6
INSPECT A/F SENSOR CIRCUIT FOR SHORT TO GROUND
•  A/F sensor connector is disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side) and body ground:
―  A/F sensor terminal B
―  A/F sensor terminal D
―  A/F sensor terminal F
•  Is there continuity?
Yes
If the short to ground circuit could be detected:
•  Repair or replace the wiring harness for a possible short to ground.
If the short to ground circuit could not be detected:
•  Replace the PCM (short to ground in PCM internal circuit).
Go to Step 9.
No
Go to the next step.
7
INSPECT PCM CONNECTOR CONDITION
•  Disconnect the PCM connector.
•  Inspect for poor connection (such as damaged/pulled-out pins, and corrosion).
•  Is there any malfunction?
Yes
Repair or replace the terminal and/or connector, then go to Step 9.
No
Go to the next step.
8
INSPECT A/F SENSOR
•  Reconnect the A/F sensor and PCM 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 2.0, MZR 2.5].)
No
Go to the next step.
9
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to 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 2.0, MZR 2.5].)
No
DTC troubleshooting completed.