DTC P0137 [L3]: Notes

DTC P0137 (L3) DETECTION CONDITION & POSSIBLE CAUSES

DTC P0137	HO2S circuit low input
DETECTION CONDITION	The PCM monitors input voltage from HO2S. If the input voltage from the HO2S sensor is below 0.1 V with HO2S fuel injection feedback value is 3% or more for 35.2 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 above 70°C {158°F}. Fuel injector control in HO2S closed loop control HO2S heater control is ON. Intake air volume is 4 g/s {0.5 lb/min} or more. 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}. HO2S heater control is ON. Diagnostic support note This is a continuous monitor (A/F sensor, HO2S). 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. DTC is stored in the PCM memory.
POSSIBLE CAUSE	HO2S connector or terminal malfunction PCM connector or terminal malfunction Open circuit in wiring between HO2S terminal A and PCM terminal 2Q Short to body ground circuit in wiring between HO2S terminal A and PCM terminal 2Q Open circuit in wiring between HO2S terminal B and PCM terminal 2AV HO2S malfunction PCM malfunction

DTC P0137

HO2S circuit low input

DETECTION CONDITION

The PCM monitors input voltage from HO2S. If the input voltage from the HO2S sensor is below 0.1 V with HO2S fuel injection feedback value is 3% or more for 35.2 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 above 70°C {158°F}.
  - Fuel injector control in HO2S closed loop control
  - HO2S heater control is ON.
  - Intake air volume is 4 g/s {0.5 lb/min} or more.
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}.
  - HO2S heater control is ON.

Diagnostic support note

This is a continuous monitor (A/F sensor, HO2S).
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.
DTC is stored in the PCM memory.

POSSIBLE CAUSE

HO2S connector or terminal malfunction
PCM connector or terminal malfunction
Open circuit in wiring between HO2S terminal A and PCM terminal 2Q
Short to body ground circuit in wiring between HO2S terminal A and PCM terminal 2Q
Open circuit in wiring between HO2S terminal B and PCM terminal 2AV
HO2S malfunction
PCM malfunction