Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

CHECK THE PCM FOR OTHER DTCS
1. Turn the ignition on.
2. With the scan tool, read the PCM DTCs.
  Are there any other DTCs present?
  
  Yes
  - Repair the other DTCs before continuing.
  - Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Go To 2
CHECK THE FUEL SYSTEM FOR A LEAK
1. Turn the ignition off.
2. Visually inspect the entire fuel system for signs of a leak.
  Is there any evidence of leakage?
  
  Yes
  - Repair as necessary in accordance with the service information.
  - Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Go To 3
CHECK THE FUEL SYSTEM FOR CONTAMINATION
1. Check the Fuel System for contamination. Refer to DIESEL FUEL SYSTEM CONTAMINATION .
  Is there any evidence of contamination?
  
  Yes
  - Repair as necessary in accordance with the Service Information.
  - Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Go To 4
CHECK THE VEHICLE FOR PROPER OPERATING CONDITIONS
1. Determine the environmental conditions at or near the time the DTC set.
  Has the vehicle been operated or cold soaked in ambient temperatures below freezing?
  
  Yes
  - Go To 5
  No
  - Go To 7
CHECK THE FUEL SYSTEM FOR GELLED FUEL BY PERFORMING THE IN-TANK LIFT PUMP FLOW TEST
NOTE:
Before performing the IN-TANK FUEL LIFT PUMP FLOW test, verify that the fuel level in the fuel tank is above 1/4 full. If fuel tank is not above 1/4 full the pump will take in air causing the test results to be inaccurate.
1. Disconnect the low pressure fuel supply line from the High Pressure Fuel Pump. Connect the (special tool #8978A, Decay Tool, Fuel) to the low pressure fuel supply line.
  WARNING:
  To reduce the risk of fire and serious possible serious or fatal injury, place the Reservoir Assembly 534960 (3) on the floor and out of the way so that it is not a trip hazard.
2. Perform the following to purge air from the system:
  - With the scan tool, actuate the In-Tank Fuel Lift Pump Module.
  - Open the Flow Test Valve and allow the fuel to flow into the Reservoir for 15 seconds, then close the Flow Test Valve.
  - Turn the ignition off.
  - Disconnect, empty, and then reconnect the Reservoir Assembly.
3. Perform the following three times to find the average flow rate:
  - With the scan tool, actuate the In-Tank Fuel Lift Pump Module.
  - Open the Flow Test Valve for 15 seconds, then close the Valve.
  - Turn the ignition off.
  - Measure and record the amount of fuel in the Reservoir Assembly.
  - Disconnect, empty, and then reconnect the Reservoir Assembly.
4. Add the three recorded measurements and then divide the total by three to calculate the average flow rate.
  NOTE:
  The flow rate specification is 750 ml in 15 seconds.
  
  Does the average flow rate meet or exceed the specification?
  
  Yes
  - If the vehicle exhibited symptoms related to fuel gelling such as hard start, start and stall, and/or low power, but no longer exhibits these symptoms, fuel gelling may have been present but corrected itself. The fuel temperature may have increased through normal operation or if the vehicle was parked inside a warm building. Verify the fuel heater is receiving power with the ignition on, and also check for proper operation of the fuel heater.
  - Add a bottle of MOPAR Premium Fuel Treatment to the Fuel Tank.
  - Then, Go To 7
  No
  - Leave the Fuel Decay Tester installed. Remove the fuel filter and inspect for fuel gelling/wax build-up and other contaminants. If wax build-up is found, the fuel has gelled. Replace the fuel filter and correct the fuel gelling accordingly before any further testing. Verify the fuel heater is receiving power with the ignition on, and also check for proper operation of the fuel heater.
  - If no wax build-up or signs of fuel gelling is found, replace the Fuel Filter/Water Separator in accordance with the Service Information.
  - Then, Go To 6
RECHECK THE FUEL SYSTEM FOR PROPER IN-TANK FUEL LIFT PUMP FLOW
1. Perform the following to purge air from the system:
  - With the scan tool, actuate the In-Tank Fuel Lift Pump Module.
  - Open the Flow Test Valve for 15 seconds, then close the Valve.
  - Turn the ignition off.
  - Disconnect, empty, and then reconnect the Reservoir Assembly.
2. Perform the following three times to find the average flow rate:
  - With the scan tool, actuate the In-Tank Fuel Lift Pump Module.
  - Open the Flow Test Valve for 15 seconds, then close the valve.
  - Turn the ignition off.
  - Measure and record the amount of fuel in the Reservoir Assembly.
  - Disconnect, empty, and then reconnect the Reservoir Assembly.
3. Add the three recorded measurements and then divide the total by three to calculate the average flow rate.
  NOTE:
  The flow rate specification is 750 ml in 15 seconds.
  
  Does the average flow rate meet or exceed the specification?
  
  Yes
  - Repair complete. But, add a bottle of MOPAR Premium Fuel Treatment to the Fuel Tank.
  - Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Use the wiring diagram as a guide to check the In-Tank Fuel Lift Pump wiring for an open, high resistance, or short to ground. If the In-Tank Fuel Lift Pump wiring is okay, remove the fuel tank and replace the In-Tank Fuel Lift Pump Module in accordance with the Service Information. Also, add a bottle of MOPAR Premium Fuel Treatment to the Fuel Tank.
  - Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
CHECK THE FUEL DELIVERY SYSTEM FOR PROPER OPERATION
1. Refer to CHECKING THE FUEL DELIVERY SYSTEM and perform the CHECKING THE FUEL DELIVERY SYSTEM diagnostic procedure.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .