
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.
58
DRIVEABILITY
P-0133 1/1 O2S SLOW RESPONSE ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
8 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 (Sensor Ground) Circuit between O2S Connector
(Sensor Ground) and PCM Connector (Sensor Ground).
Is the voltage drop reading below 0.10 VDC?All
Ye s®Replace the O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Repair poor connection (high resistance) on O2 Sensor Ground
Circuit.
Perform VERIFICATION TEST VER-5A3.
59
DRIVEABILITY
P-0133 1/1 O2S SLOW RESPONSE ÐContinued
ProCarManuals.com

Symptom:
P-0135 O2S HEATER FAILURE
When Monitored and Set Condition:
P-0135 O2S HEATER FAILURE
When Monitored: With the ignition key off, after the engine cools down.
Set Condition: No sensor output signal is received when the PCM powers up the sensor
heater.
POSSIBLE CAUSES
1/1 O2 SENSOR CONNECTOR DAMAGED
1/1 O2 SENSOR GND CIRCUIT OPEN
ASD RELAY OUTPUT CIRCUIT OPEN
1/1 O2 SENSOR FAILURE
1/1 O2 SENSOR HEATER ELEMENT FAILURE
1/1 O2S HEATER FAILURE 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 2
No®Go To 3
2 Turn Ignition On (Engine Off), wait three minutes.
With the DRB , monitor the O2 Sensor voltage for a few minutes until the voltage
stabilizes between .4 and .6 volts.
With the DRB, actuate the O2 Heater Test.
Monitor O2 voltage for up to two minutes.
Is the O2 Sensor voltage still between .4 and .6 volts?All
Ye s®Go To 4
No®Go To 3
3 At this time the 1/1 O2S HEATER FAILURE 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 DATA pay particular attention to the fault setting
conditions, such as speed, temp, load, and map vacuum.
Does the 1/1 O2S HEATER FAILURE reoccur?All
Ye s®Go To 4
No®1/1 O2S Heater failure no longer exists.
Perform VERIFICATION TEST VER-5A3.
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DRIVEABILITY
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TEST ACTION APPLICABILITY
4 Disconnect the 1/1 O2 Sensor Connector.
Check connectors - Clean / repair as necessary.
Is any terminal corroded, damaged, pushed out or miswired?All
Ye s®Repair or replace as necessary.
Perform VERIFICATION TEST VER-5A3.
No®Go To 5
5 Turn Ignition On (Engine Off).
Disconnect the 1/1 O2 Sensor Connector.
Check connectors - Clean / repair as necessary.
With the DRB, actuate the ASD Relay.
Using a voltmeter, measure the ASD Relay Output Circuit at the O2 Sensor
Connector (harness side).
Is the voltage above 10.0 volts?All
Ye s®Go To 6
No®Repair the open ASD Relay Output Circuit.
Perform VERIFICATION TEST VER-5A3.
6 Disconnect the 1/1 O2 Sensor Connector.
Check connectors - Clean / repair as necessary.
Using an ohmmeter, measure the O2 Sensor Heater Element at the O2 Sensor
Connector (component side).
Is the resistance between 4 and 7 ohms?All
Ye s®Go To 7
No®Replace the 1/1 O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
7 Disconnect the 1/1 O2 Sensor Connector.
Check connectors - Clean / repair as necessary.
Using an ohmmeter, measure from the Heater Ground Circuit to ground at the O2
Sensor Connector (harness side).
Is the resistance below 5.0 ohms?All
Ye s®Replace the 1/1 O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Repair the open 1/1 O2 Sensor Ground Circuit.
Perform VERIFICATION TEST VER-5A3.
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DRIVEABILITY
P-0135 O2S HEATER FAILURE ÐContinued
ProCarManuals.com

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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DRIVEABILITY
ProCarManuals.com

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 1/2 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 DATA pay particular attention to the fault setting
conditions, such as speed, temp, load, and map vacuum.
Does the 1/2 O2S SLOW RESPONSE reoccur?All
Ye s®Go To 5
No®The 1/2 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.
69
DRIVEABILITY
P-0139 1/2 O2S SLOW RESPONSE ÐContinued
ProCarManuals.com

TEST ACTION APPLICABILITY
8 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 (Sensor Ground) Circuit between O2S Connector
(Sensor Ground) and PCM Connector (Sensor Ground).
Is the voltage drop reading below 0.10 VDC?All
Ye s®Replace the O2 Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Repair poor connection (high resistance) on O2 Sensor Ground
Circuit.
Perform VERIFICATION TEST VER-5A3.
70
DRIVEABILITY
P-0139 1/2 O2S SLOW RESPONSE ÐContinued
ProCarManuals.com

Symptom:
P-0141 1/2 O2S HEATER FAILURE
When Monitored and Set Condition:
P-0141 1/2 O2S HEATER FAILURE
When Monitored: With the ignition key off, after the engine cools down.
Set Condition: No sensor output signal is received when the PCM powers up the sensor
heater.
POSSIBLE CAUSES
1/2 O2 SENSOR CONNECTOR DAMAGED
1/2 O2 SENSOR GND CIRCUIT OPEN
ASD RELAY OUTPUT CIRCUIT OPEN
1/2 O2 SENSOR FAILURE
1/2 O2 SENSOR HEATER ELEMENT FAILURE
1/2 O2S HEATER FAILURE 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 2
No®Go To 3
2 Turn Ignition On (Engine Off), wait three minutes.
With the DRB, monitor the O2 Sensor voltage for a few minutes until the voltage
stabilizes between .4 and .6 volts.
With the DRB, actuate the O2 Heater test.
Monitor O2 voltage for up to two minutes.
Is the O2 Sensor voltage still between .4 and .6 volts?All
Ye s®Go To 3
No®Go To 4
3 At this time the 1/2 O2S HEATER FAILURE 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 DATA pay particular attention to the fault setting
conditions, such as speed, temp, load, and map vacuum.
Does the 1/2 O2S HEATER FAILURE reoccur?All
Ye s®Go To 4
No®1/2 O2S Heater failure no longer exists.
Perform VERIFICATION TEST VER-5A3.
73
DRIVEABILITY
ProCarManuals.com