Diagnostic Test

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

CHECK FOR AN ACTIVE DTC
1. Ignition on, engine not running.
2. With the scan tool, erase DTCs in the PCM.
3. Monitor the scan tool for at least two minutes.
4. Cycle the ignition key off and on several times, leaving the ignition on for at least 10 seconds at a time.
5. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK FOR OTHER DTCS
1. Refer to the recorded DTCs.
  Are DTCs P0192 or P0193 active or pending?
  
  Yes
  - Perform the applicable diagnostic procedure(s). Refer to DTC INDEX .
  No
  - Go To 3
CHECK THE FUEL RAIL PRESSURE SENSOR (FPS) SIGNAL FOR FROPER VOLTAGE DROP
1. Turn the ignition off.
2. Using a voltmeter, backprobe the FPS signal wire (leave the harness connector attached to the sensor).
3. Turn the ignition on, engine not running.
4. Turn the ignition off while observing the voltage drop for at least 20 seconds.
  After the ignition is turned off for 20 seconds, does the voltage drop to a range between 424-609mv?
  
  Yes
  - Go To 5
  No
  - Go To 4
CHECK THE FUEL PRESSURE REGULATOR FOR PROPER STATIC LEAK BACK CONDITION
WARNING:
The fuel system is under a constant pressure (even with the engine off). Before testing or servicing any fuel system hose, fitting or line, the fuel system pressure must be released. Failure to follow these instructions can result in possible serious or fatal injury.
1. Disconnect the fuel return line at the Fuel Rail return fitting (next to the Fuel Pressure Regulator).
2. Cap the end of the fuel return line to keep debris from entering the system and fuel from leaking out.
3. Connect a hose to the end of the Fuel Rail.
4. Place the end of the hose into a measurement bottle.
5. Crank the engine, shut it off if it starts.
6. Again, crank the engine, shut if off if it starts.
7. Observe the fuel flow during this procedure.
  NOTE:
  The Fuel Pressure Regulator (FPR) should be closed during cranking. There may be residual fluid as the engine starts. But, very little or no fuel should be present during Cranking and Off.
  
  Was there fuel flowing out the end of the hose into the measurement bottle during Cranking or Off?
  
  Yes
  - Replace the Fuel Pressure Regulator in accordance with the Service Information. Refer to REGULATOR, FUEL PRESSURE, REMOVAL .
  - Then, Go To Standard Procedure, Check Diesel Fuel System Contamination. Refer to DIESEL FUEL SYSTEM CONTAMINATION .
  No
  - Go To Standard Procedure, Check Diesel Fuel System Contamination. Refer to DIESEL FUEL SYSTEM CONTAMINATION .
CHECK THE FUEL RAIL PRESSURE SENSOR FOR PROPER OPERATION
1. Disconnect the Fuel Rail Pressure Sensor harness connector.
2. With the scan tool, select View DTCs.
  NOTE:
  The scan tool should display a P0193-Fuel Rail Pressure Sensor High DTC as active with the connector disconnected.
  
  Does the scan tool display P0193-Fuel Rail Pressure Sensor High DTC as active with the connector disconnected?
  
  Yes
  - Replace the Rail Fuel Pressure Sensor in accordance with the Service Information.
  - Perform the PCM VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Repair the poor connections.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .