Symptom:
P-0131 1/1 O2 SENSOR VOLTAGE SHORTED TO GROUND
When Monitored and Set Condition:
P-0131 1/1 O2 SENSOR VOLTAGE SHORTED TO GROUND
When Monitored: With the ignition key off, after the O2 Sensor cools down; and after the
next key on provided that it is a cold start (coolant temperature less than 38 degrees C
(100.4 degrees F)) and ambient temperature within 13 degrees C (7.2 degrees F) of coolant
temperature.
Set Condition: The upstream O2 Sensor Signal voltage is below 0.156 volt prior to O2
Sensor Heater test (cool down period), and O2 voltage less than 0.156 volt after the key on
in the subsequent start.
POSSIBLE CAUSES
1/1 02 SENSOR VOLTAGE LOW
1/1 O2S SIGNAL CIRCUIT SHORT TO GROUND
1/1 O2S SIGNAL CKT SHORT TO GROUND CIRCUIT
1/1 O2 SENSOR DEFECTIVE
PCM DEFECTIVE (1/1 O2S)
TEST ACTION APPLICABILITY
1 Ignition Off
Turn ignition on.
With the DRB, monitor the Upstream O2 Sensor voltage for a few minutes.
Wait three minutes or until the voltage stabilizes (between 0.4 and 0.6 volt).
With the DRB, monitor the Upstream O2 Sensor voltage.
Is the Upstream O2 Sensor voltage below 0.156 volt?All
Ye s®Go To 2
No®The condition required to set this trouble code is not present at
this time.
Perform Powertrain Verification Test VER-5A.
2 Ignition Off
Disconnect the Upstream O2 Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Key on.
With the DRB, monitor the Upstream O2 Sensor voltage.
Is the Upstream O2 Sensor voltage below 0.156 volts?All
Ye s®Go To 3
No®Replace the Upstream O2 Sensor.
Perform Powertrain Verification Test VER-5A.
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Symptom:
P-0132 1/1 O2 SENSOR SHORTED TO VOLTAGE
When Monitored and Set Condition:
P-0132 1/1 O2 SENSOR SHORTED TO VOLTAGE
When Monitored: With the engine running for more than 2 minutes and coolant
temperature above 76 degrees C (170 degrees F).
Set Condition: The Upstream Oxygen Sensor Signal voltage is above 1.2 volts.
POSSIBLE CAUSES
1/1 O2 SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE
1/1 O2 SEN HARNESS INTERMITTENT SHORT TO VOLTAGE
1/1 O2 SENSOR CONNECTOR OBSERVABLE DEFECT (A)
1/1 O2 SENSOR CONNECTOR OBSERVABLE DEFECT (B)
1/1 O2 SENSOR HARNESS OBSERVABLE DEFECT
1/1 O2 SENSOR DEFECTIVE
TEST ACTION APPLICABILITY
1 Start the engine.
With the DRB, read the Upstream O2 Sensor voltage.
Is the Upstream O2 Sensor voltage above 1.2 volts?All
Ye s®Go To 2
No®Go To 5
2 Ignition Off
Disconnect the Upstream O2 Sensor.
Note: Check connectors - Clean/repair as necessary.
Start the engine.
With the DRB, read the Upstream O2 Sensor Voltage.
Is the Upstream O2 Sensor voltage above 1.2 volts?All
Ye s®Repair the Upstream O2 Sensor Signal Circuit for a short to
voltage. If ok, replace the PCM.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
3 Ignition Off
Disconnect the Upstream O2 Sensor.
Note: Check connectors - Clean/repair as necessary.
Is any Terminal damaged, pushed out or miswired?All
Ye s®Repair or replace as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 4
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Symptom:
P-0133 1/1 O2S SLOW RESPONSE
When Monitored and Set Condition:
P-0133 1/1 O2S SLOW RESPONSE
When Monitored: With engine temperature greater than 63 degrees C (147 degrees F),
after reaching vehicle speed of 16 kmh (10 mph), and throttle remaining open (off idle), for
2 minutes bring vehicle to a stop and allow engine to idle with transmission in drive (auto)
or in neutral (manual).
Set Condition: The Oxygen Sensor Signal voltage is switching from below 0.27 volt to
above 0.62 volt and back fewer times than required.
POSSIBLE CAUSES
ENGINE MECHANICAL PROBLEM
1/1 O2 SENSOR GROUND CKT HIGH RESISTANCE
1/1 O2 SENSOR GROUND CKT POOR CONNECTION
1/1 O2 SENSOR SIGNAL CKT HIGH RESISTANCE
1/1 O2 SENSOR SIGNAL CKT POOR CONNECTION
1/1 O2 SENSOR SLOW RESPONSE
EXHAUST LEAK
1/1 O2S SLOW RESPONSE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1 With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 5
No®Go To 2
2 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Sensor Ground) Circuit between O2S Connector
(Sensor Ground) and PCM Connector (Sensor Ground).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 3
No®Repair poor connection (high resistance) on O2 Sensor Ground
Circuit.
Perform VERIFICATION TEST VER-5A3.
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TEST ACTION APPLICABILITY
3 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Signal) Circuit between O2S Connector (O2S
Signal) and PCM Connector (O2S Signal).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 4
No®Repair poor connection (high resistance) on O2S Signal Circuit.
Perform VERIFICATION TEST VER-5A3.
4 At this time the 1/1 O2S SLOW RESPONSE does not exist or is an intermittent
problem.
With the DRB, read the FREEZE FRAME DATA.
With this screen, attempt to duplicate the condition that has set this fault.
While using FREEZE FRAME pay particular attention to the fault setting condi-
tions, such as speed, temp, load, and map vacuum.
Does the 1/1 O2S SLOW RESPONSE reoccur?All
Ye s®Go To 5
No®The 1/1 O2S SLOW RESPONSE no longer exists.
Perform VERIFICATION TEST VER-5A3.
5 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Start the Engine.
NOTE: Check the exhaust for excessive smoke caused by oil or coolant
consumption.
Is there an oil or coolant consumption condition present?All
Ye s®Repair engine mechanical as necessary and replace O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Go To 6
6 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Start the Engine.
Check the Exhaust System for leaks between the Engine and the catalyst.
Are there any leaks?All
Ye s®Repair or replace leaking Exhaust System as necessary.
Perform VERIFICATION TEST VER-5A3.
No®Go To 7
7 The following are possible causes for O2 Sensor Slow Response: exhaust leak, fuel
contamination, O2 sensor failure, electrical wiring connectors, electrical mechanical,
and O2 heater failure.
Turn Ignition On (Engine Off).
Using a voltmeter, backprobe O2S (Signal) Circuit between O2S Connector (O2S
Signal) and PCM Connector (O2S Signal).
Is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 8
No®Repair poor connection (high resistance) on O2S Signal Circuit.
Perform VERIFICATION TEST VER-5A3.
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DRIVEABILITY
P-0133 1/1 O2S SLOW RESPONSE ÐContinued
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Symptom:
P-0134 1/1 O2 SENSOR STAYS AT CENTER
When Monitored and Set Condition:
P-0134 1/1 O2 SENSOR STAYS AT CENTER
When Monitored: With the engine running for more than 2 minutes and engine
temperature greater than 76 degrees C (170 degrees F).
Set Condition: The Upstream Oxygen Sensor Signal voltage is between 0.35 volt and 0.55
volt for 1.5 minutes.
POSSIBLE CAUSES
O2 SENSOR 1/1 GROUND CIRCUIT OPEN
O2 SENSOR 1/1 SIGNAL CIRCUIT OPEN
1/1 O2 SENSOR WIRING HARN INTER DEFECT
1/1 O2 SENSOR WIRING HARN OBS DEFECT
O2 SENSOR 1/1 DEFECTIVE
PCM DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition Off
Start the engine and allow it to reach normal operating temperature.
With the DRB in actuator tests, set RPM to 1500.
In sensors, read the Upstream Oxygen Sensor State.
Is the Upstream O2 Sensor level switching?All
Ye s®Go To 2
No®Go To 4
2 Ignition Off
Start the engine and allow it to reach normal operating temperature.
Using the DRB, set the engine speed to 1500 RPM.
With the DRB, read the Upstream O2 Sensor level.
Wiggle Upstream O2 Sensor Connector and Harness.
While wiggling the Harness, monitor the DRB display.
At any time was the Upstream O2 Sensor state locked at center?All
Ye s®Repair the open Harness or Connector that caused the O2 Sensor
state to stay at center.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
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Symptom:
P-0137 1/2 O2 SENSOR VOLTAGE SHORTED TO GROUND
When Monitored and Set Condition:
P-0137 1/2 O2 SENSOR VOLTAGE SHORTED TO GROUND
When Monitored: With the ignition key off, after the O2 Sensor cools down; and after the
next key on provided that it is a cold start (coolant temperature less than 38 degrees C
(100.4 degrees F) and ambient temperature within 13.7 degrees C (7.2 degrees F) of coolant
temperature.
Set Condition: The Downstream O2 Sensor Signal voltage is below 0.156 volt prior to O2
Sensor Heater test (cool down period), and O2 voltage less than 0.156 volt after the key on
in the subsequent start.
POSSIBLE CAUSES
1/2 02 SENSOR VOLTAGE LOW
1/2 O2S SIGNAL CIRCUIT SHORT TO GROUND
1/2 O2S SIGNAL CKT SHORT TO GROUND CIRCUIT
1/2 O2 SENSOR DEFECTIVE
PCM DEFECTIVE (1/2 O2S)
TEST ACTION APPLICABILITY
1 Ignition Off
Turn ignition on.
With the DRB, monitor the Downstream O2 Sensor voltage for a few minutes.
Wait three minutes or until the voltage stabilizes (between 0.4 and 0.6 volt).
With the DRB, monitor the Downstream O2 Sensor voltage.
Is the Downstream O2 Sensor voltage below 0.156 volt?All
Ye s®Go To 2
No®The condition required to set this trouble code is not present at
this time.
Perform Powertrain Verification Test VER-5A.
2 Ignition Off
Disconnect the Downstream O2 Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Key on.
With the DRB, monitor the Downstream O2 Sensor voltage.
Is the Downstream O2 Sensor voltage below 0.156 volts?All
Ye s®Go To 3
No®Replace the Downstream O2 Sensor.
Perform Powertrain Verification Test VER-5A.
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Symptom:
P-0138 1/2 O2 SENSOR SHORTED TO VOLTAGE
When Monitored and Set Condition:
P-0138 1/2 O2 SENSOR SHORTED TO VOLTAGE
When Monitored: With the engine running for more than 2 minutes and coolant
temperature above 76 degrees C (170 degrees F).
Set Condition: The Downstream Oxygen Sensor Signal voltage is above 1.2 volts.
POSSIBLE CAUSES
1/2 O2 SENSOR SIGNAL CIRCUIT SHORT TO VOLTAGE
1/2 O2 SEN HARNESS INTERMITTENT SHORT TO VOLTAGE
1/2 O2 SENSOR CONNECTOR OBSERVABLE DEFECT (A)
1/2 O2 SENSOR CONNECTOR OBSERVABLE DEFECT (B)
1/2 O2 SENSOR HARNESS OBSERVABLE DEFECT
1/2 O2 SENSOR DEFECTIVE
TEST ACTION APPLICABILITY
1 Start the engine.
With the DRB, read the Downstream O2 Sensor voltage.
Is the Downstream O2 Sensor voltage above 1.2 volts?All
Ye s®Go To 2
No®Go To 5
2 Ignition Off
Disconnect the Downstream O2 Sensor.
Note: Check connectors - Clean/repair as necessary.
Start the engine.
With the DRB, read the Downstream O2 Sensor Voltage.
Is the Upstream O2 Sensor voltage above 1.2 volts?All
Ye s®Repair the Downstream O2 Sensor Signal Circuit for a short to
voltage. If ok, replace the PCM.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
3 Ignition Off
Disconnect the Downstream O2 Sensor.
Note: Check connectors - Clean/repair as necessary.
Is any Terminal damaged, pushed out or miswired?All
Ye s®Repair or replace as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 4
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Symptom:
P-0139 1/2 O2S SLOW RESPONSE
When Monitored and Set Condition:
P-0139 1/2 O2S SLOW RESPONSE
When Monitored: With the engine running, engine at normal operating temperature,
ambient air temperature greater than þ7ÉC (20ÉF) and vehicle odometer is greater than
6437 Kilometers (4000 miles).
Set Condition: The Oxygen Sensor Signal voltage does not exceed 0.53 volts and does not
fall below 0.35 volts once during the drive cycle.
POSSIBLE CAUSES
ENGINE MECHANICAL PROBLEM
1/2 O2 SENSOR GROUND CKT HIGH RESISTANCE
1/2 O2 SENSOR GROUND CKT POOR CONNECTION
1/2 O2 SENSOR SIGNAL CKT HIGH RESISTANCE
1/2 O2 SENSOR SIGNAL CKT POOR CONNECTION
1/2 O2 SENSOR SLOW RESPONSE
EXHAUST LEAK
1/2 O2S SLOW RESPONSE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1 With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 5
No®Go To 2
2 Turn Ignition On (Engine Off).
During the following voltage drop measurement, wiggle wires between O2S Connec-
tor and PCM Connector.
Using a voltmeter, backprobe O2S (Sensor Ground) Circuit between O2S Connector
(Sensor Ground) and PCM Connector (Sensor Ground).
While wiggling wires, is the voltage drop reading below 0.10 VDC?All
Ye s®Go To 3
No®Repair poor connection (high resistance) on O2 Sensor Ground
Circuit.
Perform VERIFICATION TEST VER-5A3.
68
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