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TEST ACTION APPLICABILITY
13 Ignition Off
Inspect the Chassis Fuel Supply Line to the engine for a kink or restriction.
Is the line kinked or restricted?All
Ye s®Release the fuel pressure. Repair the Fuel Line as necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 14
14 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Remove the Fuel Pressure Gauge from the Fuel Rail.
Adjust a shop air hose to 40 psi.
Remove the Fuel Filter.
Using shop air, inspect the Fuel Filter passage by attempting to blow air through
inlet.
Is the Fuel Filter restricted?All
Ye s®Replace the Fuel Filter.
Perform Powertrain Verification Test VER-2A.
No®Replace the Fuel Pump and Regulator Assembly.
Perform Powertrain Verification Test VER-2A.
15 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Relieve the Fuel Pressure.
Tee-in Fuel Pressure Gauge into the Fuel Supply Hose using Tool #6433.
Turn Ignition On.
With the DRB, actuate the ASD Fuel System test.
Record the Fuel Pressure reading.
Is the Fuel Pressure above 53 psi?ENGINE - 3.0L V6
Ye s®Go To 16
No®Go To 18
16 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Remove the Fuel Pressure Gauge from the Fuel Rail.
Remove the Fuel Return Line between the Fuel Tank and Filter.
Adjust a shop air hose to 40 psi.
Using shop air, inspect the Fuel Line by attempting to blow air through it.
Is the Fuel Return Line restricted?All
Ye s®Replace the Fuel Return Line.
Perform Powertrain Verification Test VER-2A.
No®Go To 17
17 If there are no potential causes remaining, the Fuel Pressure Regulator is assumed
to be defective.
View repair options.All
Repair
Replace the Fuel Pressure Regulator.
Perform Powertrain Verification Test VER-2A.
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DRIVEABILITY
* CHECKING FUEL DELIVERY ÐContinued
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TEST ACTION APPLICABILITY
18 Ignition Off
Inspect the Chassis Fuel Supply Line to engine for a kink or restriction.
Is the Fuel Line kinked or restricted?ENGINE - 3.0L V6
Ye s®Release the Fuel Pressure. Repair the Fuel Line as necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 19
19 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Install Fuel Pressure Gauge between Fuel Tank and Fuel Filter.
Key on.
With the DRB, actuate the ASD Fuel System test.
Is fuel pressure at least 5 psi higher than the previously recorded pressure?ENGINE - 3.0L V6
Ye s®Release the Fuel Pressure. Replace the Fuel Filter.
Perform Powertrain Verification Test VER-2A.
No®Go To 20
20 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the fuel pressure.
Install Fuel Pressure Gauge between Fuel Tank and Fuel Filter.
Key on.
With the DRB, actuate the ASD Fuel System test.
Is fuel pressure at least 5 psi higher than the previously recorded pressure?ENGINE - 3.0L V6
Ye s®Test Complete.
No®Release the Fuel Pressure. Replace the Fuel Pump and Regulator
Assembly.
Perform Powertrain Verification Test VER-2A.
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DRIVEABILITY
* CHECKING FUEL DELIVERY ÐContinued
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Symptom:
* CHECKING IDLE AIR CONTROL MOTOR
POSSIBLE CAUSES
ENGINE SPEED WITHIN TOLERANCE
IAC MOTOR CONNECTOR OBSERVABLE DEFECT
ENGINE HAS VACUUM LEAKS
IAC MOTOR DEFECTIVE
TEST ACTION APPLICABILITY
1 Engine Running
With the DRB in actuator tests, set the engine speed to 1400 RPM and then to 900
RPM.
Did the engine RPM go from 1400 RPM to 900 RPM?All
Ye s®With the DRB, stop all tests, test complete.
No®Go To 2
2 Engine Running
Inspect the engine for any vacuum leak(s).
Is there any vacuum leaks?All
Ye s®Repair Vacuum Leak(s) as necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 3
3 Turn the ignition off.
Disconnect the IAC motor harness connector.
Start the engine and allow it to idle.
Using a test light connected to ground, probe the IAC Driver #1 circuit.
Repeat the above test for the remaining IAC Driver circuits.
Did the test light turn on and off at any time for each IAC driver circuit?All
Ye s®Go To 4
No®Go To 5
4 Turn the ignition off.
Disconnect the IAC motor harness connector.
Start the engine and allow it to idle.
Using a test light connected to battery positive, probe the IAC Driver #1 circuit.
Repeat the above test for the remaining IAC Driver circuits.
Did the test light turn on and off at any time for each IAC driver circuit?All
Ye s®Go To 6
No®Go To 8
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DRIVEABILITY
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Symptom:
* CHECKING INTAKE AIR TEMPERATURE SENSOR
POSSIBLE CAUSES
INTAKE AIR TEMPERATURE SENSOR DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
Do not allow more than 5 minutes delay between next 2 steps.
With the DRB, read the Intake Air Temperature Sensor and record the reading.
Turn Ignition off.
Remove the IAT Sensor, then proceed to next step.
Using a Temperature Probe, quickly measure intake temperature inside IAT Sensor
opening.
Is the IAT Sensor within ±12 degrees C (10 degrees F) of the probe reading?ENGINE - 2.0L
and 2.4L I-4 DOHC
Ye s®Test Complete.
No®Replace the Intake Air Temperature Sensor.
Perform Verification Test VER-2A.
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DRIVEABILITY
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Symptom:
* CHECKING MAP SENSOR CALIBRATION
POSSIBLE CAUSES
MAP SENSOR DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition Off
Tee-in a Vacuum Gauge to a Manifold Vacuum source.
Start the engine.
Allow engine to idle.
Note: If engine will not idle, maintain a constant RPM above idle.
Using the DRB, read MAP Sensor Vacuum.
Is the reading within 1 inch of the teed-in Vacuum Gauge?All
Ye s®Go To 2
No®Replace the MAP Sensor.
Perform Verification Test VER-2A.
2 Ignition Off
Disconnect the MAP Sensor Harness Connector.
Ignition On.
Using a voltmeter, measure the 5±volt supply circuit.
Is the voltage above 4.0 volts?All
Ye s®Test Complete.
No®Repair the open 5±volt supply circuit.
Perform Verification Test VER-2A.
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Symptom:
* CHECKING MINIMUM IDLE AIR FLOW
POSSIBLE CAUSES
MINIMUM AIR FLOW IS WITHIN ACCEPTABLE RANGE
THROTTLE BODY DEFECTIVE (MIN AIR FLOW OUT OF RANGE)
TEST ACTION APPLICABILITY
1 Start the engine and allow it to reach operating temperature.
Perform the Minimum Air Flow test as described in service information.
Is idle RPM within the range shown in the chart?All
Ye s®Throttle Body minimum air flow is set correctly.
No®Go To 2
2 Ignition Off
Remove Throttle Body per service information.
Note: Clean Throttle Body in a well ventilated area and wear rubber gloves.
While holding the Throttle open, spray entire Throttle Body Bore with Mopar parts
cleaner.
Using a soft scuff pad, clean the Throttle Body Bore and Throttle Plate.
Using compressed air, dry the Throttle Body and install Throttle Body on manifold.
Start the engine and allow it to reach operating temperature.
With the DRB, enter System Test and perform the Minimum Air Flow Test.
Is the idle RPM within the range shown in the chart?All
Ye s®Test Complete.
No®Replace Throttle Body.
Perform Verification Test VER-2A.
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Symptom:
* CHECKING OXYGEN SENSOR HEATER
POSSIBLE CAUSES
1/2 O2 SENSOR VOLTAGE BTWN 0.4 V & 0.6 V
1/1 O2 SENSOR DEFECTIVE
1/2 O2 SENSOR DEFECTIVE
ASD RELAY OUTPUT CIRCUIT OPEN (1/1 O2 SEN)
ASD RELAY OUTPUT CIRCUIT OPEN (1/2 O2 SEN)
HEATER GROUND CIRCUIT OPEN (1/1 O2 SEN)
HEATER GROUND CIRCUIT OPEN (1/2 O2 SEN)
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, actuate the ASD O2 Sensor Heater test.
Wait two minutes for O2 Sensor voltage to stabilize.
Read the Upstream O2 Sensor voltage.
Is the voltage of the Upstream O2 Sensor between 0.4 and 0.6 volts?All
Ye s®Go To 2
No®Go To 5
2Note: The O2 Sensor voltage staying between 0.4 V and 0.6 V indicates a
problem with that Sensor Circuit.
Ignition Off
Disconnect the Upstream O2 Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Turn key on.
With the DRB, actuate the O2 Sensor Heater test.
Using a Voltmeter, measure the ASD Relay Output Circuit at Sensor Connector.
Is the voltage above 10.0 volts?All
Ye s®Go To 3
No®Repair the open ASD Relay Output Circuit from O2 sensor
connector back to splice.
Perform Powertrain Verification Test VER-2A.
3 Ignition Off
Disconnect the Upstream O2 Sensor Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance between the Heater Ground Circuit and
a good ground.
Is the resistance below 5.0 ohms?All
Ye s®Go To 4
No®Repair the open Heater Ground Circuit to the Upstream O2
Sensor.
Perform Powertrain Verification Test VER-2A.
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Symptom:
* CHECKING PARK/NEUTRAL POSITION SWITCH
POSSIBLE CAUSES
DISPLAY SHOWS9P/N9AND9D/R9
TRANSMISSION RANGE SENSOR DEFECTIVE
PARK/NEUTRAL POSITION SWITCH SENSE CIRCUIT OPEN
PARK/NEUTRAL SWITCH SENSE CIRCUIT SHORT TO GROUND
PCM DEF (P/N POSN SW)
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, read Park/Neutral Position Switch state.
While moving the gear selector through all gear positions, watch DRB display.
Does the display show9P/N9and9D/R9?All
Ye s®Park/Neutral Position Switch normal, test pass.
No®Go To 2
2 Ignition Off
Disconnect the Powertrain Control Module.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between the Park/Neutral Position Switch Sense Circuit at
the Powertrain Control Module Connector and ground.
While moving gear selector through all gear positions, watch the ohmmeter.
Did the display stay below 5.0 ohms at all times?All
Ye s®Go To 3
No®Go To 5
3 Ignition Off
Disconnect the negative Battery cable.
Disconnect the Powertrain Control Module.
Disconnect the Transmission Control Module.
Measure the resistance between the Park/Neutral Position Switch Sense Circuit at
the PCM harness connector and ground.
Ignition On.
Move the gear selector through all gear positions.
Did the ohmmeter display above 5.0 ohms to below 5.0 ohms?All
Ye s®Replace the Powertrain Control Module.
Perform Powertrain Verification Test VER-2A.
No®Go To 4
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