Symptom:
P1282 FUEL PUMP RELAY CONTROL CIRCUIT
When Monitored and Set Condition:
P±1282 FUEL PUMP RELAY CONTROL CIRCUIT
When Monitored: With the ignition key on and battery voltage greater than 10 volts.
Set Condition: An open or shorted condition is detected in the fuel pump relay control
circuit.
POSSIBLE CAUSES
FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN
FUEL PUMP RELAY DEFECTIVE
FUEL PUMP RELAY CONTROL CIRCUIT OPEN
FUEL PUMP RELAY CONTROL CIRCUIT SHORT TO GROUND
FUEL PUMP RELAY WIRING HARNESS INTER DEF
FUEL PUMP RELAY WIRING HARNESS OBS DEF
PCM DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, actuate the Fuel Pump Relay.
Is the Fuel Pump Relay clicking?All
Ye s®Go To 2
No®Go To 4
2 Ignition On, Engine Not Running
With the DRB actuate the Fuel Pump Relay.
Wiggle the Wiring Harness from the Relay to the PCM.
Did the Fuel Pump Relay clicking stop or become erratic while wiggling the wires?All
Ye s®Repair Circuit as necessary where wiggling caused the clicking to
become erratic.
Perform Powertrain Verification Test VER-2A.
No®Go To 3
3 Ignition Off
Using the schematic as a guide, inspect the Wiring and Connectors.
Were any problems found?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-2A.
No®Test Complete.
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DRIVEABILITY
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TEST ACTION APPLICABILITY
4 Ignition Off
Disconnect the Fuel Pump Relay.
Note: Check connectors - Clean/repair as necessary.
Ignition On, Engine Not Running
Using a Voltmeter, measure the Fused Ignition Switch Output Circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 5
No®Repair the open Fused Ignition Switch Output Circuit.
Perform Powertrain Verification Test VER-2A.
5 Ignition Off
Disconnect the Fuel Pump Relay.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure across Terminals 85 and 86 of the Fuel Pump Relay for
resistance.
Is the resistance between 50 and 90 ohms?All
Ye s®Go To 6
No®Replace Fuel Pump Relay.
Perform Powertrain Verification Test VER-2A.
6 Ignition Off
Disconnect the Powertrain Control Module Connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the Fuel Pump Relay.
Note: Check connectors - Clean/repair as necessary
Using an Ohmmeter, measure the Fuel Pump Relay Control Circuit for resistance.
Is the resistance below 5.0 ohms?All
Ye s®Go To 7
No®Repair the open Fuel Pump Relay Control Circuit.
Perform Powertrain Verification Test VER-2A.
7 Ignition Off
Disconnect the PCM Connector.
Note: Check connectors - Clean/repair as necessary.
Disconnect the Fuel Pump Relay.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the Fuel Pump Relay Control Circuit to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Fuel Pump Relay Control Circuit for a short to ground.
Perform Powertrain Verification Test VER-2A.
No®Go To 8
8 Ignition off.
If there are no potential causes remaining, the PCM is assumed to be defective.
View repair options.All
Repair
Replace the PCM.
Perform Powertrain Verification Test VER-2A.
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DRIVEABILITY
P1282 FUEL PUMP RELAY CONTROL CIRCUIT ÐContinued
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Symptom:
P-1486 EVAP LEAK MONITOR PINCHED HOSE FOUND
When Monitored and Set Condition:
P-1486 EVAP LEAK MONITOR PINCHED HOSE FOUND
When Monitored: Amb temp bet 4 deg C (40deg F) & 32 deg C (90deg F), & coolant w/in
±12 deg C (10deg F) of amb. If PCM suspects pinch, no fault until runs evap purge flow
mon. Purge flow monitored w/eng temp >76 deg C (170deg F), engine in closed loop, idle 2
min, no low fuel, MAP <15.7 in. merc, & baro alt <8000 ft.
Set Condition: LDP must pass stricter evap system test first. No air flow through the
evaporative system is detected by the evap monitor.
POSSIBLE CAUSES
FUEL TANK TO EVAP CANISTER HOSE PINCHED
LDP PRESSURE HOSE BLOCKAGE
PURGE SOLENOID TO EVAP CANISTER HOSE PINCHED
LEAK DETECTION PUMP BLOCKAGE
EVAPORATIVE CANISTER BLOCKAGE LDP SIDE
EVAPORATIVE CANISTER BLOCKAGE SOLENOID SIDE
EVAP LEAK MONITOR PINCHED HOSE DOES NOT REOCCUR
TEST ACTION APPLICABILITY
1NOTE: Replacing the Powertrain Control Module will not correct this
problem.
With the DRB, read the DTCs.
Is the GLOBAL GOOD TRIP counter displayed and equal to zero?All
Ye s®Go To 3
No®Go To 2
2 At this time the Evap Leak Monitor Pinched Hose Found does not exist or is an
intermittent problem.
With the DRB, read the FREEZE FRAME.
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 Evap Leak Monitor Pinched Hose Found reoccur?All
Ye s®Go To 3
No®Evap Leak Monitor Pinched Hose Found no longer exists.
Perform VERIFICATION TEST VER-6A.
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DRIVEABILITY
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TEST ACTION APPLICABILITY
6 To perform this test you will need Miller Tool Kit #6872A and #6922.
Caution: Refer to safety information.
If disconnected, reconnect the Vacuum Connector at the Purge Solenoid.
Perform Evaporative System Pressure Pump Self Test that is specified on the tester
cover.
Connect the Evap Pressure Pump Supply to Gas Cap Adapter and install on vehicle.
Start Engine.
With the DRB, go to LDP SYSTEM TEST and follow instructions on the screen.
Using Pressure Tool #6872A, set Pressure Hold to Open, and set Vent to Closed.
Turn Pump Timer On.
Allow Pressure Pump to build pressure up to at least 149H2O.
Remove hose at Evap Canister that goes to Purge Solenoid.
Did pressure drop when hose was disconnected?All
Ye s®Repair the pinched hose from the Purge Solenoid to the Evap
Canister.
Perform VERIFICATION TEST VER-6A.
No®Go To 7
7 To perform this test you will need Miller Tool Kit #6872A and #6922.
Caution: Refer to safety information.
Perform Evaporative System Pressure Pump Self Test that is specified on the tester
cover.
Connect the Evap Pressure Pump Supply to Gas Cap Adapter and install on vehicle.
Start Engine.
With the DRB, go to LDP SYSTEM TEST and follow instructions on the screen.
Using Pressure Tool #6872A, set Pressure Hold to Open, and set Vent to Closed.
Turn Pump Timer On.
Allow Pressure Pump to build pressure up to at least 149H2O.
Remove hose at Evap Canister that goes to Fuel Tank.
Did pressure drop when hose was disconnected?All
Ye s®Replace the Evaporative Canister.
Perform VERIFICATION TEST VER-6A.
No®Repair the pinched hose from the Gas Tank to the Evap Canister.
Perform VERIFICATION TEST VER-6A.
202
DRIVEABILITY
P-1486 EVAP LEAK MONITOR PINCHED HOSE FOUND ÐContinued
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Symptom:
* CHECKING FOR OXYGEN SENSOR SWITCHING
POSSIBLE CAUSES
O2 SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
ENGINE VACUUM ABNORMAL
FUEL DELIVERY SYSTEM DEFECTIVE
O2 SENSOR DEFECTIVE
AIR INLET SYSTEM RESTRICTED
TEST ACTION APPLICABILITY
1 Engine Running
Note: the Engine must be running and at normal operating temperature.
Note: The Downstream O2 Sensor should switch slower than the Upstream
O2 Sensor.
With the DRB, read the O2 Sensor voltages for 10 seconds or more.
Are the O2 Sensor voltages switching normally?All
Ye s®Test Complete.
No®Go To 2
2 Engine Running
Note: The Engine must be running and at normal operating temperature.
Note: The Downstream O2 Sensor should switch slower than the Upstream
O2 Sensor.
With the DRB, read the O2 Sensor voltages for 10 seconds or more.
Is the Upstream O2 Sensor locked9LEAN9?All
Ye s®Go To 3
No®Go To 9
3 Ignition On, Engine Not Running
With the DRB, read the O2 Sensor Signal voltages.
Is the voltage below 0.10 volts for the Upstream or Downstream O2 Sensor?All
Ye s®Go To 4
No®Go To 7
4 Engine Running
Allow the Engine to idle.
Inspect the Engine for any abnormal vacuum conditions.
Are there any abnormal vacuum conditions?All
Ye s®Repair abnormal Engine Vacuum condition as required.
Perform Powertrain Verification Test VER-2A.
No®Go To 5
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TEST ACTION APPLICABILITY
5 Ignition Off
Disconnect the Upstream or Downstream O2 Sensor Connector that the voltage is
below 0.10 volts.
Note: Check connectors - Clean/repair as necessary.
Disconnect the Powertrain Control Module.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance between the O2 Sensor Signal Circuit
and a good ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the O2 Sensor Signal Circuit for a short to ground.
Perform Powertrain Verification Test VER-2A.
No®Go To 6
6 If there are no potential causes remaining, the Upstream or Downstream O2 Sensor
is assumed to be defective.
View repair options.All
Repair
Replace the Upstream or Downstream O2 Sensor that was below
0.10 volts.
Perform Powertrain Verification Test VER-2A.
7 Engine Running
Allow the Engine to idle.
Inspect the Engine for any abnormal vacuum conditions.
Are there any abnormal vacuum conditions?All
Ye s®Repair abnormal Engine Vacuum condition as required.
Perform Powertrain Verification Test VER-2A.
No®Go To 8
8 Engine Running
With the DRB, reset the Adaptive Fuel Memory.
Note: The engine must be running and at normal operating temperature.
Note: The Downstream O2 Sensor should switch slower than the Upstream
O2 Sensor.
With the DRB, read the O2 Sensor voltages for 10 seconds or more.
Are the O2 Sensor voltages switching normally?All
Ye s®Test Complete.
No®Refer to symptom * CHECKING THE ENGINE MECHANICAL
SYSTEMS in the DRIVEABILITY category.
9 Ignition Off
Install a Fuel Pressure Gauge to the Fuel Line. Use special tools if necessary.
Turn ignition on.
With the DRB, actuate the ASD Fuel System Test.
Allow Fuel Pressure to stabilize.
With the DRB, stop Fuel System Test. Monitor the Pressure Gauge for 1 minute.
Is the Fuel Pressure below 10 psi?All
Ye s®If Fuel Pump and Lines are OK, replace leaking Injector(s) as
necessary.
Perform Powertrain Verification Test VER-2A.
No®Go To 10
235
DRIVEABILITY
* CHECKING FOR OXYGEN SENSOR SWITCHING ÐContinued
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Symptom:
* CHECKING FUEL DELIVERY
POSSIBLE CAUSES
FUEL LINE RESTRICTED
FUEL FILTER DEFECTIVE
FUEL LINE RESTRICTED
FUEL PRESSURE REGULATOR DEFECTIVE
FUEL PUMP/REGULATOR ASSEMBLY DEFECTIVE
FUEL RETURN LINE DEFECTIVE
FUEL PUMP/REGULATOR ASSEMBLY DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition Off
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel Pressure.
Connect a Fuel Pressure Gauge to test port.
Ignition On, Engine Not Running
With the DRB, actuate Fuel System. Fuel Pressure should be 43 to 53 psi.
Fuel Pressure should be 43 to 53 psi.
Is the Fuel Pressure within the specification?ENGINE - 2.4L I-4
DOHC and/or EN-
GINE - 3.3L V6
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.8L V6
Ye s®Go To 2
No®Go To 5
2 Ignition Off
Note: Make sure the Gear Lever is in neutral, and the Park Brakes engaged.
Start the engine.
Monitor the Fuel Pressure Gauge in the next step.
While monitoring the pressure, momentarily snap Throttle wide open raising RPM to
above 3000.
Did the fuel pressure drop below 35 psi at all?All
Ye s®Go To 3
No®Test Complete.
3 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 4
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TEST ACTION APPLICABILITY
4 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.
5 Ignition Off.
Warning: The Fuel System must be opened and may be under high pressure.
Release the Fuel Pressure.
Connect a Fuel Pressure Gauge to test port.
Ignition On, Engine Not Running.
With the DRB, actuate Fuel System. Fuel Pressure should be 43 to 53 psi for Gasoline
Engines and 50 to 60 psi for Flexible Fuel Vehicle.
Record the Fuel Pressure reading.
Is the Fuel Pressure above the specification?ENGINE - 2.4L I-4
DOHC and/or EN-
GINE - 3.3L V6
and/or ENGINE -
3.3L V6 FFV and/or
ENGINE - 3.8L V6
Ye s®Go To 6
No®Go To 8
6 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 7
7 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.
238
DRIVEABILITY
* CHECKING FUEL DELIVERY ÐContinued
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