2000 CHRYSLER VOYAGER coolant

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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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.
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P-0139 1/2 O2S SLOW RESPONSE ÐContinued
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TEST ACTION APPLICABILITY
3 Ignition On, Engine Not Running.
With the DRB, read TPS Sensor voltage. Throttle must be against stop.
Is the voltage 0.92 or less with the Throttle closed?All
Ye s®Go To 4
No®Replace the Throttle Position Sensor.
Perform Powertrain Verification Test VER-5A.
4 Turn ignition On.
With the DRB in sensors, read the ªEngine Coolant Tmp Degº value.
Note: If engine coolant temperature is above 82ÉC (180ÉF), allow the engine
to cool until 62ÉC (150ÉF) is reached.
Start the Engine.
While monitoring the DRB, allow the engine to reach normal operating temperature
above 82ÉC (180ÉF).
Did the engine coolant temperature value reach 82ÉC (180ÉF) or above?All
Ye s®Go To 5
No®Replace the Engine Coolant Temperature Sensor.
Perform Powertrain Verification Test VER-5A.
5 Turn ignition On.
With the DRB in sensors, read the88Eng Coolant Tmp Deg'' value
Note: If engine coolant temperature is above 82ÉC (180ÉF), allow the engine
to cool until 62ÉC (150ÉF) is reached.
Start the Engine.
While monitoring the DRB, allow the engine to reach normal operating temperature
above 82ÉC (180ÉF).
Was the coolant temperature value increase a smooth transition?All
Ye s®Go To 6
No®Replace the Engine Coolant Temperature Sensor.
Perform Verificatino Test VER-5A.
6 Turn ignition off.
Connect a Vacuum Gauge to a Manifold Vacuum source.
Start the engine.
Allow the engine to idle.
Note: If engine will not idle, maintain a constant RPM above idle.
Using the DRB in Sensors, read the MAP Sensor vacuum value.
Is the DRB reading within 19of the Vacuum Gauge reading?All
Ye s®Go To 7
No®Replace the MAP Sensor.
Perform Powertrain Verification Test VER-5A.
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DRIVEABILITY
P-0171±1/1 FUEL SYSTEM LEAN ÐContinued
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TEST ACTION APPLICABILITY
3 Ignition On, Engine Not Running.
With the DRB, read TP Sensor voltage. Throttle must be against stop.
Is the voltage 0.92 or less with the Throttle closed?All
Ye s®Go To 4
No®Replace the Throttle Position Sensor.
Perform Powertrain Verification Test VER-5A.
4 Turn ignition on.
With the DRB in sensors, read the ªEng Coolant Tmp Degº value.
Note: If engine coolant temperature is above 82ÉC (180ÉF), allow the engine
to cool until 62ÉC (150ÉF) is reached.
Start the Engine.
While monitoring the DRB, allow the engine to reach normal operating temperature
above 82ÉC (180ÉF).
Did the engine coolant temperature value reach 180ÉF or above?All
Ye s®Go To 5
No®Replace the Engine Coolant Temperature Sensor.
Perform Powertrain Verification Test VER-5A.
5 Turn ignition On.
With the DRB in sensors, read the ªEng Coolant Tmp Deg'' value
Note: If engine coolant temperature is above 82ÉC (180ÉF), allow the engine
to cool until 62ÉC (150ÉF) is reached.
Start the Engine.
While monitoring the DRB, allow the engine to reach normal operating temperature
above 82ÉC (180ÉF).
Was the coolant temperature value increase a smooth transition?All
Ye s®Go To 6
No®Replace the Engine Coolant Temperature Sensor.
Perform Verification Test VER-5A.
6 Turn ignition off.
Connect a Vacuum Gauge to a Manifold Vacuum source.
Start the engine.
Allow the engine to idle.
Note: If engine will not idle, maintain a constant RPM above idle.
Using the DRB in Sensors, read the MAP Sensor vacuum value.
Is the DRB reading within 19of the Vacuum Gauge reading?All
Ye s®Go To 7
No®Replace the MAP Sensor.
Perform Powertrain Verification Test VER-5A.
7Note: Engine must be at operating temp and in closed loop to perform this
test.
Start engine and run until operating temp and closed loop mode is reached.
With the DRB under System Tests, go to ªPurge Vapors Test''. Observe the Short
Term Adaptive value and press 3 to flow.
Note: Short Term Adaptive should change.
Did the Short Term Adaptive value change?All
Ye s®Go To 8
No®Refer to symptom *CHECKING EVAPORATIVE EMISSION
SYSTEM in the DRIVEABILITY category.
80
P0172 -1/1 FUEL SYSTEM RICH ÐContinued
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TEST ACTION APPLICABILITY
4NOTE: Check the exhaust for excessive smoke from internal oil or coolant
leaks.
Is there an oil or coolant consumption condition present?All
Ye s®Repair engine mechanical as necessary and replace Catalytic
Converter.
Perform VERIFICATION TEST VER-5A3.
No®Go To 5
5NOTE: A new Downstream O2 Sensor along with an aging Upstream O2
Sensor may cause this trouble code to set.
Review vehicle repair history.
Has the Downstream O2 Sensor been replaced without replacing the Upstream O2
Sensor?All
Ye s®Replace the appropriate Upstream Oxygen Sensor.
Perform VERIFICATION TEST VER-5A3.
No®Replace the Catalytic Converter.
Perform VERIFICATION TEST VER-5A3.
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P-0420 1/1 CATALYTIC CONVERTER EFFICIENCY ÐContinued
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Symptom:
P-1195 SLOW 1/1 O2S DURING CATALYST MONITOR
When Monitored and Set Condition:
P-1195 SLOW 1/1 O2S DURING CATALYST MONITOR
When Monitored: With the engine running, coolant greater than 76 deg C (170 deg F),
open throttle, steady to slight increasing vehicle speed > 28 Km/h (18 mph) < 88 Km/h (55
mph), with a light load on the engine, for a period no less than five minutes.
Set Condition: The upstream oxygen sensor signal voltage is switching from below 0.39
volt to above 0.6 volt and back fewer times than required.
POSSIBLE CAUSES
OXYGEN SENSOR GROUND CIRCUIT OPEN
1/1 OXYGEN SENSOR CONNECTOR OBSERVABLE DEFECT
1/1 OXYGEN SENSOR DEFECTIVE
ENGINE FLUID CONSUMPTION
EXHAUST SYSTEM LEAKING
PCM CONNECTOR OBSERVABLE DEFECT
TEST ACTION APPLICABILITY
1 Start 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 Upstream O2
Sensor.
Perform Powertrain Verification Test VER-5A.
No®Go To 2
2 Start Engine
Check the Exhaust System for leaks between Engine and Catalytic Converter.
Is there any Exhaust leak?All
Ye s®Repair or replace leaking Exhaust parts as necessary.
Perform Powertrain Verification Test VER-5A.
No®Go To 3
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Symptom:
P-1281 ENGINE IS COLD TOO LONG
When Monitored and Set Condition:
P-1281 ENGINE IS COLD TOO LONG
When Monitored: Ignition key on, engine not running. Ambient temperature greater
than þ11ÉC (-11ÉF) and coolant temperature greater than þ7ÉC (19ÉF)
Set Condition: The engine does not warm to 79 degrees C (176 degrees F) while driving
for 20 minutes after start.
POSSIBLE CAUSES
ENGINE COLD TOO LONG
TEST ACTION APPLICABILITY
1 Start Engine
Drive vehicle under normal driving conditions for 20 minutes.
With the DRB, read Engine Coolant Temperature.
Did the engine warm to 79 degrees C (176 degrees F)?All
Ye s®Test Complete.
No®See pertinent service manual information for cooling system
diagnostics.
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