Inspection and Verification - NVH: Notes

1. NVH symptoms should be identified using the diagnostic tools and techniques that are available. For a list of these techniques, tools, an explanation of their uses and a glossary of common terms, refer to NOISE, VIBRATION & HARSHNESS article.
2. Verify the customer concern by operating the engine to duplicate the condition.
3. Check the engine oil level and check the oil for contamination. Low engine oil level or contaminated oil are a common cause of engine noise. If the oil is contaminated, the source of the contamination must be identified and repaired as necessary.
4. Visually inspect for obvious signs of mechanical damage. Refer to the following table.
   VISUAL INSPECTION TABLE
   
   

   Mechanical
   Loose mounting bolts, studs and nuts Damaged or leaking powertrain mounts Damaged or disconnected vacuum hoses Obstruction of cooling fan Obstruction of Front End Accessory Drive (FEAD) Obstruction of Rear End Accessory Drive (READ), if equipped Damaged or disconnected air intake components

5. If the inspection reveals obvious concerns that can be readily identified, repair as necessary.
NOTE: Make sure to use the latest scan tool software release.
6. If the cause is not visually evident, connect the scan tool to the DLC.
NOTE: The VCM LED prove out confirms power and ground from the DLC are provided to the VCM.
7. If the scan tool does not communicate with the VCM:
   • check the VCM connection to the vehicle.
   • check the scan tool connection to the VCM.
   • refer to MODULE COMMUNICATIONS NETWORK -- FUSION, MILAN & MKZ article, No Power To The Scan Tool, to diagnose no power to the scan tool.
8. If the scan tool does not communicate with the vehicle:
   • verify the ignition key is in the ON position.
   • verify the scan tool operation with a known good vehicle.
   • refer to MODULE COMMUNICATIONS NETWORK -- FUSION, MILAN & MKZ article to diagnose no response from the PCM.
9. Carry out the network test.
   • If the scan tool responds with no communication for one or more modules, refer to MODULE COMMUNICATIONS NETWORK -- FUSION, MILAN & MKZ article.
   • If the network test passes, retrieve and record continuous memory DTCs.
10. Clear the continuous DTCs and carry out the self-test diagnostics for the BCM-HVTB and PCM.
11. If the DTCs retrieved are related to the concern, go to the Battery Control Module - High Voltage Traction Battery (BCM-HVTB) DTC Table, refer to HIGH VOLTAGE TRACTION BATTERY -- FUSION HYBRID, MILAN HYBRID & MKZ HYBRID article. For all other DTCs, refer to MULTIFUNCTION ELECTRONIC MODULES -- FUSION, MILAN & MKZ article.
12. If no DTCs related to the concern are retrieved, continue the inspection and verification if a noise concern is related to the engine. For vibration concerns and noise concerns, such as powertrain mounts, air intake system and starter, GO to SYMPTOM TABLE - NVH .

In some cases, a noise may be a normal characteristic of that engine type. In other cases the noise may require further investigation. Comparing the noise to a similar year/model vehicle equipped with the same engine will aid in determining if the noise is normal or abnormal.

Once a customer concern has been identified as an abnormal engine noise, it is critical to determine the location of the specific noise. Use the EngineEAR/ChassisEAR or stethoscope to isolate the location of the noise to one of the following areas.

• Fuel injector(s)
• Upper end of engine
• Lower end of engine
• Front of engine
• Rear of engine