2006 DODGE RAM SRT-10 fuel pump

8.FUEL RETURN LINE OBSTRUCTION, DAMAGED OR DEBRIS
Check the fuel return lines for signs of obstruction, damage, or debris.
Are the fuel drain lines damaged or blocked?
Ye s>>
Repair cause of high fuel drain line restriction.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 9
9.LIFT PUMP FLOW
Perform the no trouble code*LIFT PUMP FLOW TEST. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
Did the Lift pump pass the test?
Ye s>>
Go To 10
No>>
Replace the Lift Pump.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
10.PRESSURE LIMITING VALVE
Perform the no trouble code test*PRESSURE LIMITING VALVE ON THE FUEL RAIL FOR INTERNAL LEAKS.
Did the pressure limiting valve pass the test procedure?
Ye s>>
Go To 11
No>>
Replace the Pressure Limiting Valve.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
11 .LEAKING FUEL INJECTORS OR HIGH PRESSURE CONNECTORS
Perform the no trouble test*INJECTOR RETURN FLOW TEST. (Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING)
Are any Injectors leaking or high pressure connectors leaking?
Ye s>>
Replace or repair the leaking fuel injectors or high pressure connectors.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 12
12.HIGH PRESSURE FUEL PUMP
Perform the no trouble code test*HIGH PRESSURE FUEL PUMP PERFORMANCE TEST. (Refer to 9 - ENGINE
- DIAGNOSIS AND TESTING)
Did the fuel pump pass the high pressure fuel pump performance test?
Ye s>>
Refer to the INTERMITTENT CONDITION Symptom (Diagnostic Procedure). (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
No>>
Replace the High pressure fuel pump.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

When Monitored:
When the ignition is on.
Set Condition:
The ECM detects a discrepancy between the PWM supplied to the Electronic Fuel Control Actuator and the
PWM returned from the Electronic Fuel Control Actuator.
Possible Causes
FUEL PUMP
(K181) FUEL CONTROL ACTUATOR DRIVER OPEN
(K31) RETURN CIRCUIT OPEN FROM FCA TO ECM
(K181) FUEL CONTROL ACTUATOR DRIVER CIRCUIT SHORTED TO EXTERNAL VOLTAGE
(K31) FUEL CONTROL ACTUATOR RETURN CIRCUIT SHORTED TO EXTERNAL VOLTAGE
(K31) FCA RETURN CIRCUIT SHORTED TO (K181) FCA DRIVER CIRCUIT
(K181) FUEL CONTROL ACTUATOR DRIVER CIRCUIT SHORTED TO GROUND
(K181) FUEL CONTROL ACTUATOR DRIVER CIRCUIT SHORTED TO ANOTHER CIRCUIT
(K31) FUEL CONTROL ACTUATOR RETURN CIRCUIT SHORTED TO ANOTHER CIRCUIT
INTERMITTENT CONDITION
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.FUEL PUMP
Ignition on, engine not running.
Disconnect the Fuel Control Actuator (FCA) harness connector.
Connect an incandescent test light across the Fuel Control Actuator
driver circuit and the Fuel Control Actuator return circuit at the fuel con-
trol actuator harness connector.
Observe the test light.
The ECM will perform a self test of the circuit which should momentarily
flash the test light brightly, one time, approximately 20 seconds after
being connected.
NOTE: Check connectors - Clean/repair as necessary.
NOTE: Compare test light brightness to that of a direct connection
to the battery.
Did the light flash brightly?
Ye s>>
Replace the Fuel Pump.
Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)
No>>
Go To 2

P0628-LOW VOLTAGE DETECTED AT THE FUEL LIFT PUMP
For a complete wiring diagramRefer to Section 8W.

When Monitored:
Whilethekeyison.
Set Condition:
The commanded signal to the fuel lift pump circuit in the TIPM does not matchthe feedback signal from the
fuel lift pump circuit.
Possible Causes
WIRING HARNESS
TIPM
FUEL LIFT PUMP CONTROL CIRCUIT SHORTED TO EXTERNAL VOLTAGE
FUEL LIFT PUMP CONTROL CIRCUIT OPEN
FUEL LIFT PUMP GROUND CIRCUIT OPEN
FUEL LIFT PUMP GROUND CIRCUIT SHORTED TO EXTERNAL VOLTAGE
ECM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.POWER AT TPIM
Using a voltmeter, measure the voltage on the Battery Supply wire to the TIPM.
Turn the ignition on, engine off.
Does the voltmeter show battery voltage?
No>>
Fix or replace the open circuit in the Battery Supply Circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
Ye s>>
Go To 2
2.DAMANGED WIRING HARNESS
Turn Ignition off.
Disconnect the ECM and TIPM connectors. Inspect the connectors for signs of damage or corrosion.
NOTE: Check connectors - Clean/repair as necessary.
Are any pins damaged?
Ye s>>
Fix or replace the harness
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 5
3.FUEL LIFT PUMP CONTROL CIRCUIT OPEN
Using an ohmmeter, measure the resistance of the lift pump control circuitbetween the ECM connector and the
TIPM connector.
Is the resistance less than 10 Ohms?
Ye s>>
Go To 4
No>>
Repair the open ground circuit.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

4.FUEL LIFT PUMP CONTROL CIRCUIT SHORTED TO EXTERNAL VOLTAGE
Using a voltmeter, measure the voltage between battery negative and the lift pump control circuit at the TPIM con-
nector.
Is the voltage greater than 1 volt?
No>>
Go To 5
Ye s>>
Fix or replace the harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
5.FUEL LIFT PUMP CONTROL CIRCUIT SHORTED TO OTHER CIRCUITS
Using an ohmmeter, measure the resistance between the lift pump control circuit in the ECM connector and all other
circuits in the ECM connectors.
Is the resistance less than 10 Ohms?
Ye s>>
Fix or replace the harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 6
6.FUEL LIFT PUMP CONTROL CIRCUIT SHORTED TO EXTERNAL VOLTAGE
Connect the ECM and TIPM connectors.
Using a back probing tool 6801, back probe the lift pump control circuit in from TIPM connector.
Toggle the lift pump actuator with the Electronic Service Tool.
Using a 12 volt test light connected to battery negative, check the lift pump circuit at the TIPM connector.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery.
Does the test light cycle on and off and illuminate brightly?
No>>
Replace the ECM
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
Ye s>>
Go To 7
7.FUEL LIFT PUMP DRIVER CIRCUIT SHORTED TO OTHER CIRCUITS
Using a back probing tool, back probe the lift pump control circuit in the TIPM connector.
Toggle the lift pump actuator with the scan Tool.
Using a 12 volt test light connected to battery negative, check the lift pump control circuit at the TIPM connector.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery.
Does the test light cycle on and off and illuminate brightly?
Ye s>>
Te s t c o m p l e t e .
Perform Intermittent Condition test. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING)
No>>
Replace the TPIM
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

P0629-HIGH VOLTAGE DETECTED AT THE FUEL LIFT PUMP
For a complete wiring diagramRefer to Section 8W.

When Monitored:
Whilethekeyison.
Set Condition:
The commanded signal to the fuel lift pump relay does not match the feedbacksignal from the fuel lift pump
relay.
Possible Causes
DAMAGED WIRING HARNESS
LIFT PUMP DRIVER CIRCUIT SHORTED TO GROUND
ECM
TIPM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
Diagnostic Test
1.LIFT PUMP DRIVER CIRCUIT SHORTED TO GROUND
Turn the ignition on, engine off.
Disconnect the ECM and TIPM connectors.
NOTE: Check connectors - Clean/repair as necessary.
Using an ohmmeter, measure the resistance of the lift pump driver wire between the ECM connector and ground.
Is the resistance less than 10 Ohms?
Ye s>>
Fix or repair the wire harness.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)
No>>
Go To 2
2.ECM
Turn Ignition off.
Connect the ECM and TIPM connectors.
Turn the ignition on, engine off.
Using a back probing tool 6801, back probe the lift pump logic pin in from TIPM connector.
Toggle the lift pump actuator with the Electronic Service Tool.
Using a 12 volt test light connected to battery negative, check the lift pump circuit at the TIPM connector.
NOTE: The test light must illuminate brightly.
Compare the brightness to that of a direct connection to the battery.
Does the test light cycle on and off and illuminate brightly?
Ye s>>
Go To 3
No>>
Replace the ECM.
Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

P127C-FUEL PUMP CONTROL CIRCUIT 2 LOW
For a complete wiring diagramRefer to Section 8W.