Oxygen Sensor Monitor
OBD System Description - Oxygen Sensor MonitorHO2 B1S1 Short High
DTC Description / Detecting Condition / Confirmation Procedure
P0132 refer to DTC P0132: HO2S Circuit High Voltage Sensor 1. P0132
Monitor Strategy Description
Determines if O2 sensor circuit is shorted high.
Malfunction Criteria
O2 sensor filtered voltage > 0.9521
Enable Conditions
Sensor cooled status flag = FALSE
AND Transient Conditions status flag = FALSE
AND Off-board device control = FALSE
AND Airflow ≥ 2 g/s
AND Engine stable conditions met = FALSE
AND Ignition Voltage ≥ 10 V
AND Sensor warm enough = FALSE
AND Fuel reduction active = FALSE
AND Engine running = RUN
AND Engine Run Time ≥ 10 s
AND Coolant Temperature ≥ 20 degrees C
AND Closed loop requesting stoichiometric A/F Ratio? = TRUE
AND DFCO enabled = FALSE
AND Enable Timer ≥ 3 s
Time required
Time Length and Frequency:
100 test failures within 120 test samples at 125 ms loop time.
Failure Time:
Continuous monitoring.
HO2 B1S2 Short High
DTC Description / Detecting Condition / Confirmation Procedure
P0138 refer to DTC P0138: HO2S Circuit High Voltage Sensor 2. P0138
Monitor Strategy Description
Determines if O2 sensor circuit is shorted high.
Malfunction Criteria
O2 sensor filtered voltage > 0.9521
Enable Conditions
Sensor cooled status flag = FALSE
AND Transient Conditions status flag = FALSE
AND Off-board device control = FALSE
AND Air Flow ≥ 2 g/s
AND Engine stable conditions met = FALSE
AND Ignition voltage ≥ 10 V
AND Sensor warm enough = FALSE
AND Fuel reduction active = FALSE
AND Engine running = RUN
AND Engine Run time ≥ 10 s
AND Engine coolant warm enough ≥ 20 C
AND Closed loop requesting stoichiometric A/F Ratio? = TRUE
AND DFCO enabled = FALSE
AND Enable Timer ≥ 3 s
Time required
Time Length and Frequency:
850 test failures within 1200 test samples at 125 ms loop time.
Failure Time:
Continuous monitoring.
HO2 B1S1 Short Low
DTC Description / Detecting Condition / Confirmation Procedure
P0131 refer to DTC P0131: HO2S Circuit Low Voltage Sensor 1. P0131
Monitor Strategy Description
Determines if O2 sensor circuit is shorted low.
Malfunction Criteria
O2 sensor filtered voltage < 0.0347
Enable Conditions
Sensor cooled status flag = FALSE
AND Transient Conditions status flag = FALSE
AND Off-board device control = FALSE
AND Airflow ≥ 2 g/s
AND Engine stable conditions met = FALSE
AND Ignition Voltage ≥ 10 V
AND Sensor warm enough = FALSE
AND Fuel reduction active = FALSE
AND Engine running = RUN
AND Engine Run Time ≥ 10 s
AND Coolant Temperature ≥ 20 degrees C
AND Closed loop requesting stoichiometric A/F Ratio? = TRUE
AND DFCO enabled = FALSE
AND Enable Timer ≥ 3 s
Time required
Time Length and Frequency:
100 test failures within 120 test samples at 125 ms loop time.
Failure Time:
Continuous monitoring.
HO2 B1S2 Short Low
DTC Description / Detecting Condition / Confirmation Procedure
P0137 refer to DTC P0137: HO2S Circuit Low Voltage Sensor 2. P0137
Monitor Strategy Description
Determines if O2 sensor circuit is shorted low.
Malfunction Criteria
O2 sensor filtered voltage < 0.0518
Enable Conditions
Sensor cooled status flag = FALSE
AND Transient Conditions status flag = FALSE
AND Off-board device control = FALSE
AND Airflow ≥ 2 g/s
AND Engine stable conditions met = FALSE
AND Ignition Voltage ≥ 10 V
AND Sensor warm enough = FALSE
AND Fuel reduction active = FALSE
AND Engine running = RUN
AND Engine Run Time ≥ 10 s
AND Coolant Temperature ≥ 20 degrees C
AND Closed loop requesting stoichiometric A/F Ratio? = TRUE
AND DFCO enabled = FALSE
AND Enable Timer ≥ 3 s
Time required
Time Length and Frequency:
850 test failures within 1,200 test samples at 125 ms loop time.
Failure Time:
Continuous monitoring.
HO2 B1S1 Response
DTC Description / Detecting Condition / Confirmation Procedure
P0133 refer to DTC P0133: HO2S Slow Response Sensor 1. P0133
Monitor Strategy Description
Determines O2 sensor functionality by checking its response rate.
Malfunction Criteria
Did enough switches occur?
Switch counter >= 60 counts
OR
Switch counter >= 60 counts
OR
All of these conditions must be met to "pass" the diagnostic:
Lean to Rich Ave Time < 12.8008 counts (For AT), 10 counts (For MT)
Rich to Lean Ave Time < 11.5 counts
Response Ratio Low > 0.5 counts
Response Ratio High < 2 counts
Enable Conditions
Current BLM Cell Valid? = TRUE
OR BLM Option selected = FALSE
AND Engine Speed >= 1,600 rpm
AND Engine Speed <= 4,300 rpm
AND Airflow <= 9 g/s
AND Airflow >= 40 g/s
AND Run Time > 50 s
AND Coolant Temperature > 70 degrees C
AND Stoichiometric Air/Fuel Ratio Commanded? = TRUE
AND DFCO Exit with Rich Bias Fueling = FALSE
AND TORQ Fuel Reduction in effect = FALSE
AND Disabling Faults Present = FALSE
AND Enable Timer > 2 s
Time required
Time Length and Frequency:
Data collected for 90 sec.
Failure Time:
Once data collected and calculation is completed, test results are reported and test begins again.
HO2 B1S1 Open
DTC Description / Detecting Condition / Confirmation Procedure
P0134 refer to DTC P0134: HO2S Circuit Insufficient Activity Sensor 1. P0134
Monitor Strategy Description
Determines if O2 sensor circuit is open.
Malfunction Criteria
O2 sensor voltage >= 0.2998 V
OR
O2 sensor voltage <= 0.6001 V
Enable Conditions
Sensor cooled status flag = FALSE
AND Transient Conditions status flag = FALSE
AND Off-board device control = FALSE
AND Airflow ≥ 2 g/s
AND Engine stable conditions met = FALSE
AND Ignition Voltage ≥ 10 V
AND Sensor warm enough = FALSE
AND Fuel reduction active = FALSE
AND Disabling Faults Present = FALSE
AND Engine Run Time ≥ 60 s
AND Coolant Temperature ≥ 20 degrees C
AND DFCO active = FALSE
Time required
Time Length and Frequency:
612 test failures within a 720 test samples.
Failure Time:
Continuous monitoring every 125 ms.
HO2 B1S2 Response
DTC Description / Detecting Condition / Confirmation Procedure
P0139 refer to DTC P0139: HO2S Slow Response Sensor 2. P0139
Monitor Strategy Description
Determines if Rear O2 Sensor is acceptable for Idle Catalyst Monitor use.
Malfunction Criteria
Response time for Stage 1 ICMD Fuel Shift >= 25 sec.
OR Response time for Stage 2 ICMD Fuel Shift >= 25 sec.
Enable Conditions
IF Idle Catalyst Monitor Diagnostic is enabled = TRUE
SET O2 Bank 1 Sensor 2 Response Diag. Enable Criteria Met = TRUE
Time required
Time Length and Frequency:
50 second maximum time allowed for test to complete during idle.
HO2 B1S2 Open
DTC Description / Detecting Condition / Confirmation Procedure
P0140 refer to DTC P0140: HO2S Circuit Insufficient Activity Sensor 2. P0140
Monitor Strategy Description
Determines if O2 sensor circuit is open.
Malfunction Criteria
O2 sensor voltage >= 0.4219 V
OR
O2 sensor voltage <= 0.478 V
Enable Conditions
Sensor cooled status flag = FALSE
AND Transient Conditions status flag = FALSE
AND Off-board device control = FALSE
AND Airflow ≥ 2 g/s
AND Engine stable conditions met = FALSE
AND Ignition Voltage ≥ 10 V
AND Fuel reduction active = FALSE
AND Disabling Faults Present = FALSE
AND Engine Run Time ≥ 60 s
AND Coolant Temperature ≥ 20 degrees C
AND DFCO active = FALSE
Time required
Time Length and Frequency:
1300 test failures within a 1,500 test samples.
Failure Time:
Continuous monitoring every 125 ms.