
TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the PCM harness connector.
Disconnect the IPM C4 harness connector
Measure the resistance of the ASD Output circuit between the IPM harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms.All
Ye s®Go To 4
No®Repair the ASD Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4 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.
5 Turn the ignition off.
Install a substitute relay in place of the ASD Relay.
Attempt to start the engine.
With the DRBIIIt, read DTCs.
Does the DTC reset?All
Ye s®Go To 6
No®Replace the ASD Relay.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6 Turn the ignition off.
Remove the ASD Relay from the IPM.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit in the IPM.
Does the test light illuminate?All
Ye s®Go To 7
No®Replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
7 Turn the ignition off.
Remove the ASD Relay from the IPM.
Disconnect the PCM harness connector.
Disconnect the IPM C4 harness connector.
Measure the resistance of the ASD Relay Output circuit between the IPM harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms.All
Ye s®Go To 8
No®Repair the ASD Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
199
DRIVEABILITY - GAS
P1389-NO ASD RELAY OUTPUT VOLTAGE AT PCM ÐContinued

TEST ACTION APPLICABILITY
2 To continue testing you will need Miller Tools #6872A Evap System Pressure Pump
and #8382 Gas Cap Tester Adapter.
WARNING: The test equipment is designed to be used to pressurize the
vehicles Evaporative System only. Using the equipment in a manner for
which it was not designed could be harmful.
Warning: Keep lighted cigarettes, sparks, flames, and other ignition sources
away from the test area to prevent the ignition of explosive gases. Keep the
test area well ventilated.
Note: The fuel tank should have between 20% & 80% of full to properly test
the Evap system.
Attach the power source red clip of Miller Tool #6872A to Battery (+) and the ground
black clip to Battery (-).
Perform the Evaporative System Pressure Pump self test that is specified on the
tester cover.
Remove gas cap and install Miller Tool #8382 on vehicle. Install gas cap to Miller Tool
#8382. Attach the pressure supply hose from Miller Tool #6872A to the fitting on
#8382.
Disconnect the vacuum supply hose at the Leak Detection Pump. Connect and apply
a continuous vacuum supply (i.e. 209Hg) to the Leak Detection Pump. A vacuum
pump such as an A/C recovery unit works well.
Turn the ignition on.
With the DRBIIItin System Tests, select Leak Detect Pump Test. Read instructions
and then press Enter. Select: #3 - HOLD PSI.
On Miller Tool #6872A, set the Pressure/Hold switch to Open and set the Vent switch
to Closed. Turn the pump timer On and watch the gauge.
When the gauge pressure reaches 149H2O, turn the Pressure/Hold Valve to Closed.
Turn the pump timer off.
Disconnect the hose at the EVAP Canister that goes to the Fuel Tank.
Did the pressure drop when the hose was disconnected?All
Ye s®Go To 3
No®Repair obstruction in the EVAP system between the EVAP
Canister and the fuel tank.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
3Note: All previously disconnected hose(s) reconnected.
Re-pressurize the EVAP System. On Miller Tool #6872A, set the Pressure/Hold
switch to Open and set the Vent switch to Closed. Turn the pump timer On and watch
the gauge.
When the gauge pressure reaches 149H2O, turn the Pressure/Hold Valve to Closed.
Turn the pump timer off.
Disconnect the LDP Pressure hose at the EVAP Canister. The LDP Pressure hose is
the hose that connects the Evap Canister to the Leak Detection Pump.
Did the pressure drop when the hose was disconnected?All
Ye s®Go To 4
No®Replace the EVAP Canister.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
208
DRIVEABILITY - GAS
P1486-EVAP LEAK MONITOR PINCHED HOSE FOUND ÐContinued

TEST ACTION APPLICABILITY
3WARNING: 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.
4 Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Using a 12-volt test light connected to 12-volts, probe the Ground circuit in the
Radiator Fan Relay harness connector.
Does the test light illuminate?All
Ye s®Go To 5
No®Repair the Ground circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5NOTE: Inspect the Radiator Fan fuse located in the IPM.
Turn the ignition off.
Disconnect the Radiator Fan Relay harness connector.
Measure the voltage of the Fused B+ Output circuit in the Radiator Fan Relay
harness connector.
Is the voltage above 11.0 volts?All
Ye s®Go To 6
No®Repair the Fused B+ circuit. Check and replace any open fuses.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6NOTE: Ensure the Radiator Fan Relay harness connector is connected.
Turn the ignition off.
Disconnect the PCM harness connector.
Turn the ignition on.
Using a jumper wire, momentarily jumper the Radiator Fan Relay Control circuit to
ground.
Did the Radiator Fans operate?All
Ye s®Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 7
211
DRIVEABILITY - GAS
P1491-RAD FAN CONTROL RELAY CIRCUIT ÐContinued

Symptom:
P1495-LEAK DETECTION PUMP SOLENOID CIRCUIT
When Monitored and Set Condition:
P1495-LEAK DETECTION PUMP SOLENOID CIRCUIT
When Monitored: Immediately after a cold start, with battery/ambient temperature
between 4.4ÉC (40ÉF). F and 32ÉC (90ÉF). Coolant temperature within -12ÉC (10ÉF) of
battery/ambient.
Set Condition: The state of the solenoid circuit does not match the PCM's desired state.
POSSIBLE CAUSES
WIRING HARNESS INTERMITTENT
LEAK DETECTION PUMP
FUSED IGNITION SWITCH OUTPUT
LDP SOLENOID CONTROL CIRCUIT SHORTED TO GROUND
LDP SOLENOID CONTROL CIRCUIT OPEN
PCM
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read DTC's.
Is the Good Trip displayed and equal to zero?All
Ye s®Go To 2
No®Go To 7
2 Turn the ignition off.
Disconnect the Leak Detection Pump harness connector.
Using a 12-volt test light, connect one end to the Fused Ignition Switch Output
circuit and the other end to the LDP Solenoid Control circuit.
Turn the ignition on.
With the DRBIIIt, actuate the Leak Detection Pump.
Does the test light flash on and off.All
Ye s®Replace the Leak Detection Pump.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
No®Go To 3
216
DRIVEABILITY - GAS

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Leak Detection Pump harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the Ignition Switch Output
circuit in the LDP harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 4
No®Repair the Fused Ignition Switch Output circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
4 Turn the ignition off.
Disconnect the Leak Detection Pump harness connector.
Disconnect the Powertrain Control Module harness connector.
Measure the resistance of the LDP Solenoid Control circuit in the LDP harness
connector to ground.
Is the resistance below 5.0 Ohms?All
Ye s®Repair the LDP Solenoid Control circuit for a short to ground.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
No®Go To 5
5 Turn the ignition off.
Disconnect the Leak Detection Pump harness connector.
Disconnect the Powertrain Control Module harness connector.
Measure the resistance of the LDP Solenoid Control circuit between the LDP
Solenoid harness connector and the PCM harness connector.
Is the resistance below 5.0 Ohms?All
Ye s®Go To 6
No®Repair the LDP Solenoid Control circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
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 - 6.
7 At this time, the conditions required to set the DTC are not present.
Note: Use the Freeze Frame Data to help you duplicate the conditions that
set the DTC. Pay particular attention to the DTC set conditions, such as,
VSS, MAP, ECT, and Load.
Note: Visually inspect the related wiring harness. Look for any chafed,
pierced, pinched, or partially broken wires.
Note: Visually inspect the related wire harness connectors. Look for broken,
bent, pushed out, or corroded terminals.
Note: Refer to any Technical Service Bulletins (TSB's) that may apply.
Perform a wiggle test of the LDP wiring while the circuit is actuated with the DRB.
Listen for the LDP to quit actuating. Also watch for the Good Trip Counter to change
to 0.
Were any problems found?All
Ye s®Repair wiring harness/connectors as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 6.
No®Test Complete.
217
DRIVEABILITY - GAS
P1495-LEAK DETECTION PUMP SOLENOID CIRCUIT ÐContinued

TEST ACTION APPLICABILITY
5Note: The fuel pressure must be within specification before continuing.
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.
Disconnect the fuel supply line at the fuel rail.
Connect fuel line adapter #6539(5/169) or #6631(3/89) to the disconnected fuel supply
line. Insert the other end of the adapter into a graduated container.
Caution: Do not operate the fuel pump for more than 7 seconds in the next
step. Fuel pump module reservoir may run empty and damage to the fuel
pump will result.
Note: Specification: A good fuel pump will deliver at least 1/4 liter (1/2 pint)
of fuel in 7 seconds.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test for 7 seconds.
Is the fuel pump capacity within specification?All
Ye s®Test Complete.
No®Check for a kinked/damaged fuel supply line between the fuel
tank and fuel rail. If OK, replace the fuel pump module.
Perform POWERTRAIN VERIFICATION TEST VER-1.
Caution: Stop All Actuations.
6 Turn the ignition off.
Disconnect the fuel pump module harness connector.
Turn the ignition on.
With the DRBIIIt, actuate the ASD Fuel System test.
Using a 12 volt test light connected to ground, probe the Fuel Pump Relay Output
circuit at the Fuel Pump Module harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 7
No®Go To 9
Caution: Stop All Actuations.
7 Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.
Note: Check connectors - It is critical that the connector is free from any
signs of corrosion or deformities - Clean/repair as necessary.
Using a test light connected to battery voltage, probe the Fuel Pump ground circuit
at the Fuel Pump Module harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 8
No®Repair the open/high resistance in the fuel pump ground circuit.
Perform POWERTRAIN VERIFICATION TEST VER-1.
8 If there are no possible causes remaining, view repair. All
Repair
Replace the Fuel Pump Module.
Perform POWERTRAIN VERIFICATION TEST VER-1.
229
DRIVEABILITY - GAS
*CHECKING FUEL DELIVERY ÐContinued

TEST ACTION APPLICABILITY
9 Turn the ignition off.
Remove the Fuel Pump Relay from the IPM.
With a 12 volt test light connected to ground, probe the Fuel Pump Relay Fused B+
circuit at the IPM.
Does the test light illuminate?All
Ye s®Go To 10
No®Check for an open Fuel Pump fuse, repair cause of open. If OK,
replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER-1.
10 Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.
Disconnect the IPM C8 harness connector.
Measure the resistance of the Fuel Pump Relay Output circuit from between the IPM
harness connector and the Fuel Pump Module harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 11
No®Repair the Fuel Pump Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER-1.
11NOTE: Ensure all IPM harness connectors are connected.
Turn the ignition off.
Disconnect the Fuel Pump Module harness connector.
Remove the Fuel Pump Relay from the IPM.
Measure the resistance of the Fuel Pump Relay Output circuit between the IPM and
the Fuel Pump Module harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Replace the Fuel Pump Relay.
Perform POWERTRAIN VERIFICATION TEST VER-1.
No®Replace the IPM Fused & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER-1.
230
DRIVEABILITY - GAS
*CHECKING FUEL DELIVERY ÐContinued

Symptom:
*CHECKING PCM POWER AND GROUND CIRCUITS
POSSIBLE CAUSES
PCM FUSED B+ CIRCUIT
PCM FUSED IGNITION SWITCH OUTPUT CIRCUIT
PCM GROUND CIRCUITS
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the PCM harness connector.
Using a 12-volt test light connected to ground, probe the PCM Fused B+ circuit in the
PCM harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 2
No®Repair the Fused B+ circuit.
Perform POWERTRAIN VERIFICATION TEST VER-1.
2 Turn the ignition off.
Disconnect the PCM harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, probe the PCM Fused Ignition Switch
Output circuit in the PCM harness connector.
Does the test light illuminate brightly?All
Ye s®Go To 3
No®Repair the Ignition Switch Output circuit
Perform POWERTRAIN VERIFICATION TEST VER-1.
3 Turn the ignition off.
Disconnect the PCM harness connector.
Using a 12-volt test light connected to battery voltage, probe the PCM ground circuits
in the PCM harness connector.
Does the test light illuminate brightly?All
Ye s®Test Complete.
No®Repair the PCM ground circuits.
Perform POWERTRAIN VERIFICATION TEST VER-1.
234
DRIVEABILITY - GAS