
TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Measure the resistance of the O2 Sensor Heater ground circuit in the O2 Sensor
harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 5
No®Repair the O2 Sensor Heater ground circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
With the DRBIIIt, actuate the O2 Heater Test.
Measure the voltage of the ASD Relay Output circuit in the O2 Sensor harness
connector.
Is the voltage above 11.0 volts?All
Ye s®Go To 6
No®Repair the ASD Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
7WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
89
DRIVEABILITY - GAS
P0141-1/2 O2 SENSOR HEATER FAILURE ÐContinued

TEST ACTION APPLICABILITY
10 Turn the ignition on.
Disconnect the O2 Sensor harness connector.
With the DRBIIIt, monitor the O2 Sensor voltage.
Is the O2 Sensor voltage between 0.40 to 0.60 volts?All
Ye s®Replace the O2 Sensor
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 11
11 Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the O2 Sensor Signal circuit in the PCM harness connector
to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the O2 Sensor Signal for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 12
12 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
13 Turn the ignition off.
Warning: The fuel system is under a constant pressure (even with the engine
off). Before testing or servicing any fuel system hose, fitting or line, the fuel
system pressure must be released.
Raise vehicle on hoist, and disconnect the fuel pressure line at the fuel pump module.
Install special 5/16 fuel line adapter tool #6539 between disconnected fuel line and
the fuel pump module.
Attach a fuel pressure test gauge to the T fitting on tool #6539.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test and observe the fuel pressure
gauge.
NOTE: Fuel pressure specification is 400 KPa +/- 34 KPa (58.2 psi +/- 5 psi).
Is the fuel pressure within specification?All
Ye s®Repair or replace fuel supply line as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 14
Caution: Stop All Actuations.
14 Turn the ignition off.
Warning: The fuel system is under a constant pressure (even with the engine
off). Before testing or servicing any fuel system hose,fitting or line, the fuel
system pressure must be released.
Remove the Fuel Pump Module and inspect the Fuel Inlet Strainer.
Is the Fuel Inlet Strainer plugged?All
Ye s®Replace the Fuel Pump Inlet Strainer.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 15
93
DRIVEABILITY - GAS
P0171-1/1 FUEL SYSTEM LEAN ÐContinued

TEST ACTION APPLICABILITY
15 If there are no possible causes remaining, view repair. All
Repair
Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
16NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
94
DRIVEABILITY - GAS
P0171-1/1 FUEL SYSTEM LEAN ÐContinued

TEST ACTION APPLICABILITY
10 Check for any of the following conditions/mechanical problems.
AIR INDUCTION SYSTEM - must be free from restrictions.
ENGINE VACUUM - must be at least 13 inches in neutral
ENGINE VALVE TIMING - must be within specifications
ENGINE COMPRESSION - must be within specifications
ENGINE EXHAUST SYSTEM - must be free of any restrictions or leaks.
ENGINE PCV SYSTEM - must flow freely
TORQUE CONVERTER STALL SPEED - must be within specifications
POWER BRAKE BOOSTER - no internal vacuum leaks
FUEL - must be free of contamination
FUEL INJECTOR - plugged or restricted injector; control wire not connected to
correct injector
Are there any engine mechanical problems?All
Ye s®Repair as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
11 Turn the ignition on.
Disconnect the O2 Sensor harness connector.
With the DRBIIIt, monitor the O2 Sensor voltage.
Is the O2 Sensor voltage between 0.4 to 0.6 volts?All
Ye s®Replace the O2 Sensor
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 12
12 Turn the ignition off.
Disconnect the PCM harness connector.
Disconnect the O2 Sensor harness connector.
Measure the resistance of the O2 Sensor Signal circuit between the PCM harness
connector and the O2 Sensor harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 13
No®Check for O2 Sensor Signal circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
13WARNING: KEEP CLEAR OF THE ENGINE'S MOVING PARTS.
Turn the ignition off.
Disconnect the O2 Sensor harness connector.
Start the engine.
Measure the voltage of the O2 Sensor Signal circuit in the PCM harness connector.
Is the voltage above 0.60 volt?All
Ye s®Repair the O2 Sensor Signal for a short to voltage.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 14
14 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
98
DRIVEABILITY - GAS
P0172-1/1 FUEL SYSTEM RICH ÐContinued

TEST ACTION APPLICABILITY
15NOTE: Check for contaminates that may have damaged the O2 Sensor:
contaminated fuel, unapproved silicone, oil and coolant.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
99
DRIVEABILITY - GAS
P0172-1/1 FUEL SYSTEM RICH ÐContinued

TEST ACTION APPLICABILITY
4 Turn the ignition off.
Disconnect the Fuel Injector harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the Fuel Injector driver circuit between the Fuel Injector
harness connector and the PCM harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 5
No®Repair the Fuel Injector driver circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5 Turn the ignition off.
Disconnect the Fuel Injector harness connector.
Disconnect the PCM harness connector.
Measure the resistance between ground and the Fuel Injector driver circuit in the
Fuel Injector harness connector.
Is the resistance below 100k ohms?All
Ye s®Repair the Fuel Injector driver circuit for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 6
6 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module Module in
accordance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
7WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
102
DRIVEABILITY - GAS
P0201-INJECTOR #1 CONTROL CIRCUIT ÐContinued

TEST ACTION APPLICABILITY
5WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
6 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Turn the ignition on.
Measure the voltage of the 8 Volt Supply circuit in the CKP Sensor harness connector.
Is the voltage between 7.5 and 8.5 volts?All
Ye s®Go To 7
No®Go To 15
7 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Turn the ignition on.
Measure the voltage of the CKP Sensor Signal circuit in the CKP Sensor harness
connector.
Is the voltage between 4.5 and 5.0 volts?All
Ye s®Go To 8
No®Go To 10
8 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the Sensor Ground circuit between the CKP Sensor
harness connector and the PCM harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 9
No®Repair the Sensor Ground circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
9NOTE: Inspect the slots on the flywheel for damage. If a problem is found
repair as necessary.
If there are no possible causes remaining, view repair.All
Repair
Replace the Crankshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
11 0
DRIVEABILITY - GAS
P0320-NO CRANK REFERENCE SIGNAL AT PCM ÐContinued

TEST ACTION APPLICABILITY
10 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the CKP Sensor Signal circuit in the CKP Sensor harness
connector to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the CKP Sensor Signal circuit for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 11
11 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance of the CKP Sensor Signal circuit between the CKP Sensor
harness connector and the PCM harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 12
No®Repair the CKP Sensor Signal circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
12 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Turn the ignition on.
Measure the voltage of the CKP Sensor Signal circuit in the CKP Sensor harness
connector.
Is the voltage above 5.0 volts?All
Ye s®Repair the CKP Sensor Signal circuit for a short to battery
voltage.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 13
13 Turn the ignition off.
Disconnect the CKP Sensor harness connector.
Disconnect the PCM harness connector.
Measure the resistance between the CKP Sensor Signal circuit and the 8 Volt Supply
circuit in the CKP Sensor harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Repair the CKP Sensor Signal circuit shorted to the 8 Volt Supply
circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 14
14 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
111
DRIVEABILITY - GAS
P0320-NO CRANK REFERENCE SIGNAL AT PCM ÐContinued