DTC P0137 [MTX, LF ATX (FS5A-EL)]

id0102b4805000

DTC P0137

HO2S circuit low input
DETECTION CONDITION
•  The PCM monitors input voltage from HO2S. If the input voltage from the HO2S is below 0.1 V for 41.6 s the PCM determines that circuit input is low.
MONITORING CONDITIONS
―  A/F sensor, HO2S, A/F sensor heater, HO2S heater and TWC repair verification drive mode
―  Following conditions are met.
•  Engine speed is above 1,500 rpm.
•  Engine coolant temperature is above 70 °C {158 °F}.
•  Fuel injector control in HO2S closed loop control.
•  The PCM monitors the input voltage from the HO2S when the following conditions are met. Under the following monitoring conditions, if the input voltage from the HO2S does not even exceed 0.1 V though the short term fuel trim is controlled up to 20.5 % for 9.6 s, the PCM determines that sensor circuit input is low.
MONITORING CONDITIONS
―  A/F sensor, HO2S, A/F sensor heater, HO2S heater and TWC repair verification drive mode
―  Following conditions are met for above 20.8 s.
•  Engine speed is above 1,500 rpm.
•  Engine coolant temperature is above 70 °C {158 °F}.
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 first drive cycle.
•  FREEZE FRAME DATA is available.
•  DTC is stored in the PCM memory.
POSSIBLE CAUSE
•  HO2S malfunction
•  Short to ground in wiring between HO2S terminal A and PCM terminal 2Q
•  Open circuit in wiring between HO2S terminal A and PCM terminal 2Q
•  Open circuit in wiring between HO2S terminal B and PCM terminal 2P
•  PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION
1
VERIFY FREEZE FRAME DATA AND DIAGNOSTIC MONITORING TEST RESULTS HAVE BEEN RECORDED
•  Have FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS (HO2S related) been recorded?
Yes
Go to the next step.
No
Record the FREEZE FRAME DATA and DIAGNOSTIC MONITORING TEST RESULTS on the repair order, then go to the next step.
2
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.
3
VERIFY RELATED PENDING AND STORED DTC
•  Turn the ignition switch off, then to the ON position. (Engine off)
•  Verify the related PENDING CODE or stored DTCs using M-MDS.
•  Is other DTC present?
Yes
Go to the appropriate DTC troubleshooting procedures.
(SeeDTC TABLE [MTX, LF ATX (FS5A-EL)].)
No
Go to the next step.
4
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
•  Is DTC P0137 on FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to troubleshooting for DTC on FREEZE FRAME DATA.
(See DTC TABLE [MTX, LF ATX (FS5A-EL)].)
5
INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND AT HARNESS
•  Turn the ignition switch to the off.
•  Disconnect HO2S and PCM connectors.
•  Verify the continuity between following HO2S terminal A and body ground.
•  Is there continuity?
Yes
Replace short to ground circuit, then go to step 8.
No
Go to the next step.
6
INSPECT HO2S CIRCUIT FOR OPEN CIRCUIT
•  Turn the ignition switch to the off.
•  Inspect for continuity between the following terminals:
―  HO2S terminal A and PCM terminal 2Q
―  HO2S terminal B and PCM terminal 2P
•  Is there any continuity?
Yes
Go to next step.
No
Repair or replace harness for open circuit, then go to Step 8.
7
INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO AT HO2S
•  HO2S connector disconnected.
•  Verify the continuity between following HO2S sensor terminal A (part side) and body ground.
•  Is there continuity?
Yes
Replace suspected HO2S then go to the next step.
No
Go to the next step
8
VERIFY TROUBLESHOOTING OF DTC P0137 COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from memory using the M-MDS.
•  Perform the KOEO or KOER self-test
•  Is the PENDING CODE same DTC present?
Yes
Replace PCM, then go to the next step.
(See PCM REMOVAL/INSTALLATION [LF, L3].)
No
Go to next step.
9
VERIFY AFTER REPAIR PROCEDURE
•  Perform the “AFTER REPAIR PROCEDURE”.
•  Is there any DTC present?
Yes
Go to applicable DTC inspection.
(SeeDTC TABLE [MTX, LF ATX (FS5A-EL)].)
No
Troubleshooting completed.