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 DTC P0131 [L8, LF, L3]

DTC P0131 [L8, LF, L3]

id0102a1804600

DTC P0131

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 input voltage is above 1.0 V for 2 s, the PCM determines that the A/F sensor circuit voltage is low.
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 is available.
• Are any DTCs is stored in the PCM memory.

POSSIBLE CAUSE

• A/F sensor malfunction
• Connector or terminal malfunction
• Open circuit in wiring harness between A/F sensor terminal 1C and PCM terminal 2Z
• Short to ground in wiring harness between A/F sensor terminal 1C and PCM terminal 2Z
• Open circuit in wiring harness between A/F sensor terminal 1B and PCM terminal 2AC
• Short to ground in wiring harness between A/F sensor terminal 1B and PCM terminal 2AC
• Open circuit in wiring harness between A/F sensor terminal 1A and PCM terminal 2AD
• Short to ground in wiring harness between A/F sensor terminal 1A and PCM terminal 2AD
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAS BEEN RECORDED
• Has FREEZE FRAME DATA been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME on the repair order, then go to the next step.
2
VERIFY RELATED REPAIR 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.
3
VERIFY RELATED PENDING OR STORED DTC
• Turn the ignition switch off, then to the ON position (Engine off).
• Verify the pending code or stored DTCs using the WDS or equivalent.
• Are other DTCs present?
Yes
Go to the appropriate DTC troubleshooting procedures. (See DTC TABLE [L8, LF, L3].)
No
Go to the next step.
4
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is the DTC P0131 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to troubleshooting procedures for DTC on FREEZE FRAME DATA. (See DTC TABLE [L8, LF, L3].)
5
INSPECT A/F SENSOR CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch 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 terminal, then go to Step 10.
No
Go to the next step.
6
INSPECT A/F SENSOR CIRCUIT FOR SHORT TO GROUND
• Turn the ignition switch off.
• Inspect for continuity between the following terminals and body ground:
- A/F sensor terminal 1A (wiring harness-side) and body ground
- A/F sensor terminal 1B (wiring harness-side) and body ground
- A/F sensor terminal 1C (wiring harness-side) and body ground
• Is there continuity?
Yes
Repair or replace the wiring harness for a possible short to ground, then go to Step 10.
No
Go to the next step.
7
INSPECT A/F SENSOR
• Inspect the A/F sensor.
• Is there any malfunction?
Yes
Replace the A/F sensor, then go to Step 10.
No
Go to the next step.
8
INSPECT PCM CONNECTOR FOR POOR CONNECTION
• Turn the ignition switch off.
• Disconnect the PCM connector.
• Inspect for poor connection (such as damaged/pulled-out pins, corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 10.
No
Go to the next step.
9
INSPECT A/F SENSOR CIRCUIT FOR OPEN CIRCUIT
• Turn the ignition switch off.
• Inspect for continuity between the following circuits:
- A/F sensor terminal 1A (wiring harness-side) and PCM terminal 2AD (wiring harness-side)
- A/F sensor terminal 1B (wiring harness-side) and PCM terminal 2AC (wiring harness-side)
- A/F sensor terminal 1C (wiring harness-side) and PCM terminal 2Z (wiring harness-side)
• Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to the next step.
10
VERIFY TROUBLESHOOTING OF DTC P0131 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Perform the KOEO or KOER self-test.
• Is the DTC P0131 present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
11
VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.