Diagnostic Test
WARNING: This page is about a different car, the 2015 RAM 1500. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR AN ACTIVE DTC NOTE:
If there are any Fuel Pressure Sensor or Fuel Pump Control Module DTCs present, repair those DTCs before proceeding with this test.
- Turn the ignition on.
- With the scan tool, read DTCs.
Is the DTC active?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
- CHECK THE FUEL SYSTEM FOR LEAKS
- Visually inspect the fuel system for signs of a fuel leak.
Were any fuel leaks found in the system?
Yes
- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 3
- Visually inspect the fuel system for signs of a fuel leak.
- CHECK THE FUEL SYSTEM PRESSURE
- Perform the diagnostic procedure for CHECKING THE FUEL DELIVERY SYSTEM. Refer to DIAGNOSIS AND TESTING
.
Were any problems found with the fuel delivery system?
Yes
- Perform the appropriate repair.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 4
- Perform the diagnostic procedure for CHECKING THE FUEL DELIVERY SYSTEM. Refer to DIAGNOSIS AND TESTING
.
- CHECK FOR EXCESSIVE RESISTANCE IN THE (K181) FUEL RAIL PRESSURE SENSOR SIGNAL CIRCUIT
- Turn the ignition off.
- Disconnect the FRPS harness connector.
- Disconnect both PCM C1 and C2 harness connectors.
- Measure the resistance of the (K181) FRPS Signal circuit between the FRPS harness connector and the PCM C1 harness connector.
Is the resistance below 3.0 Ohms?
Yes
- Go To 5
No
- Repair the (K181) FRPS Signal circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- CHECK FOR EXCESSIVE RESISTANCE IN THE (K914) FUEL RAIL PRESSURE SENSOR GROUND CIRCUIT
- Measure the resistance of the (K914) FRPS Ground circuit between the FRPS harness connector and the PCM C1 harness connector.
Is the resistance below 3.0 Ohms?
Yes
- Go To 6
No
- Repair the (K914) Sensor Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Measure the resistance of the (K914) FRPS Ground circuit between the FRPS harness connector and the PCM C1 harness connector.
- CHECK THE (F856) 5-VOLT SUPPLY CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Measure the resistance of the (F856) 5-Volt Supply circuit between the FRPS harness connector and the PCM C2 harness connector.
Is the resistance below 3.0 Ohms?
Yes
- Go To 7
No
- Repair the (F856) Sensor Ground circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- Measure the resistance of the (F856) 5-Volt Supply circuit between the FRPS harness connector and the PCM C2 harness connector.
- CHECK THE FUEL RAIL PRESSURE SENSOR
- Turn the ignition off.
- Reconnect both PCM C1 and C2 harness connectors.
- Turn the ignition on.
- With the scan tool, read DTCs.
- While monitoring scan tool, connect a jumper between the (K181) FRPS Signal circuit and the (K914) Sensor Ground circuit at the FRPS harness connector.NOTE:
The PCM should display the P018D-FUEL PRESSURE SENSOR HIGH DTC with the connector unplugged and P018C-FUEL PRESSURE SENSOR LOW DTC with the jumper in place.
Does the scan tool display the DTCs as described above?
Yes
- Replace the Fuel Rail Pressure Sensor in accordance with the Service Information.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL . Refer to PCM/ECM REPROGRAMMING - GAS .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .