DTC P0137:00 [MZR 2.0, MZR 2.5]


id0102g3300300

DTC P0137:00

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 with HO2S fuel injection feedback value is 2.7% or more for 25 s, the PCM determines that circuit input is low.
•  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 20.8 s, the PCM determines that HO2S circuit input is low.
MONITORING CONDITIONS
―  Drive Mode 03 (A/F sensor heater, HO2S heater, A/F sensor, HO2S and TWC Repair Verification Drive Mode)
―  Following conditions are met for above 20.8 s:
•  Engine speed: above 1,500 rpm
•  Engine coolant temperature: above 70 °C {158 °F}
•  HO2S heater control: ON
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
•  HO2S connector or terminals malfunction
•  Short to ground in wiring harness between HO2S terminal A and PCM terminal 2Q
•  PCM connector or terminals malfunction
•  Open circuit in wiring between the following terminals:
―  HO2S terminal A—PCM terminal 2Q
―  HO2S terminal B—PCM terminal 2AS
•  HO2S 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 P0137:00 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).
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.
No
Go to the next step.
5
INSPECT HO2S CONNECTOR CONDITION
•  Switch the ignition to off.
•  Disconnect the HO2S 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 10.
No
Go to the next step.
6
INSPECT HO2S SIGNAL CIRCUIT FOR SHORT TO GROUND
•  HO2S connector is disconnected.
•  Inspect for continuity between HO2S terminal A (wiring harness-side) and body ground.
•  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 10.
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 10.
No
Go to the next step.
8
INSPECT HO2S CIRCUIT FOR OPEN CIRCUIT
•  HO2S and PCM connectors are disconnected.
•  Inspect for continuity between the following terminals (wiring harness-side):
―  HO2S terminal A—PCM terminal 2Q
―  HO2S terminal B—PCM terminal 2AS
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness for a possible open circuit, then go to Step 10.
9
INSPECT HO2S
•  Reconnect the HO2S and PCM connectors.
•  Is there any malfunction?
Yes
Replace the HO2S, then go to the next step.
No
Go to the next step.
10
VERIFY DTC TROUBLESHOOTING COMPLETED
•  Make sure to reconnect all disconnected connectors.
•  Clear the DTC from the PCM memory using the M-MDS.
•  Perform the Drive Mode 03 (A/F sensor heater, HO2S heater, A/F sensor, HO2S and TWC Repair Verification Drive Mode).
•  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.
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.