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Diagnostic Test

  1. 1) DTC IS ACTIVE 

    Turn the ignition on.

    With the scan tool, Clear DTCs in the Powertrain Control Module (PCM).

    With the scan tool, actuate the Fuel Pump Relay Control State.

    With the scan tool, select View DTCs.

    Is the status Active for this DTC? 

    Yes 

    1. Go to  2).

    No 

    1. Refer to *CHECKING FOR AN INTERMITTENT DTC .
  2. 2) INTERNAL FUSED B(+) CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 1: Checking The Internal Fused B(+) Circuit In The Fuel Pump Relay Connector Using A 12 Volt Test Light Connected To Ground
    GC0049647Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Remove the Fuel Pump Relay.

    Turn the ignition on.

    Using a 12 volt test light connected to ground, check the Internal Fused B(+) circuit in the Fuel Pump Relay connector.

    NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

    Is the test light illuminated and bright? 

    Yes 

    1. Go to  3).

    No 

    1. Repair the Internal Fused B(+) circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  3. 3) INTERNAL FUSED IGNITION SWITCH OUTPUT (RUN-START) CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 2: Check The Internal Fused Ignition Switch Output Circuit In The Fuel Pump Relay Connector Using A 12 Volt Test Light Connected To Ground
    GC0049648Courtesy of CHRYSLER LLC

    Using a 12 volt test light connected to ground, check the Internal Fused Ignition Switch Output (Run-Start) circuit in the Fuel Pump Relay connector.

    NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

    Is the test light illuminated and bright? 

    Yes 

    1. Go to  4).

    No 

    1. Repair the Internal Fused Ignition Switch Output (Run-Start) circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  4. 4) (K31) FUEL PUMP RELAY CONTROL CIRCUIT SHORTED TO VOLTAGE 
    Fig 3: Measuring The Voltage Of The Fuel Pump Relay Control Circuit In The Fuel Pump Relay Connector
    GC0049649Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Powertrain Control Module (PCM) connector.

    Turn the ignition on.

    Measure the voltage of the (K31) Fuel Pump Relay Control circuit in the Fuel Pump Relay connector.

    Is there any voltage present? 

    Yes 

    1. Repair the (K31) Fuel Pump Relay Control circuit for a short to voltage.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  5).
  5. 5) (K31) FUEL PUMP RELAY CONTROL CIRCUIT SHORTED TO GROUND 
    Fig 4: Measuring The Resistance Between Ground And The Fuel Pump Relay Control Circuit In The Fuel Pump Relay Connector
    GC0049650Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance between ground and the (K31) Fuel Pump Relay Control circuit in the Fuel Pump Relay connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the (K31) Fuel Pump Relay Control circuit for a short to ground.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  6).
  6. 6) (K31) FUEL PUMP RELAY CONTROL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 5: Measuring The Resistance Of The Fuel Pump Relay Control Circuit Between The Fuel Pump Relay Connector And The Powertrain Control Module Harness Connector
    GC0049651Courtesy of CHRYSLER LLC

    Measure the resistance of the (K31) Fuel Pump Relay Control circuit between the Fuel Pump Relay connector and the Powertrain Control Module (PCM) harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  7).

    No 

    1. Repair the (K31) Fuel Pump Relay Control circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  7. 7) FUEL PUMP RELAY 
    Fig 6: Checking The Fuel Pump Relay Control Circuit In The Fuel Pump Relay Harness Connector Using A 12 Volt Test Light Connected To 12 Volts
    GC0049652Courtesy of CHRYSLER LLC

    Connect the Powertrain Control Module (PCM) connector.

    Turn the ignition on.

    With the scan tool, actuate the Fuel Pump Relay Control State control to the ON position.

    Using a 12 volt test light connected to 12 volts, check the (K31) Fuel Pump Relay Control circuit in the Fuel Pump Relay harness connector.

    NOTE: If the DTC is active, the actuation test may not be allowed by the PCM. If may be necessary to clear the DTCs before starting the actuation.
    NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

    Is the test light illuminated and bright? 

    Yes 

    1. Replace the Fuel Pump Relay in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  8).
  8. 8) POWERTRAIN CONTROL MODULE (PCM) 

    Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Fuel Pump Relay and the Powertrain Control Module (PCM).

    Look for any chafed, pierced, pinched, or partially broken wires.

    Look for broken, bent, pushed out or corroded terminals.

    Refer to any Technical Service Bulletins that may apply.

    Were any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .
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