Pinpoint Test L: Noise Driving Straight On Smooth Roads

Normal Operation and Fault Conditions 

Description 

• Front end noises while driving straight involve parts which rotate continuously while the road wheels are rotating. This is typically not caused by a steering gear.
• Wheel hub bearings can produce noise after achieving 56 km/h (35 mph) while driving straight if they are worn.
• Noises can also be caused by loose or un-retained parts affected by wind.

Pinpoint Test Applicability 

• This test applies to the following diagnostic concerns:
• Noises occurring from the from of the vehicle while driving straight on smooth roads

This test DOES NOT apply to any other DTC or symptom.

Diagnostic Strategy 

• To visually check for obvious parts that may be damaged within parts that are in motion during this drive event, followed up by Chassis Ears usage to further define where the noise source may be while steering (turning the steering wheel) during this drive event.

Pinpoint Test Purpose 

• To search for the components contributing to steering noises during this drive event and determine if the resulting components are defective or the noise is a normally occurring noise for this vehicle type.

• If a damaged bellows boot(s) was discovered during inspection and this pinpoint test

  DOES NOT  lead to the installation of a new EPAS gear or bellows boot(s), ADDRESS the damaged boot(s) before returning the vehicle to the customer.

Possible Sources 

• Possible rotating sources:
• Axle shafts or halfshafts
• Carrier bearing (noise is typically felt through the console)
• Drive shafts
• Transfer case assembly (if equipped)
• Wheel hub and wheel bearings (typically higher speeds)
• Possible Wind Sources:
• Air dams
• Heat shields
• Radiator ducts or shields
• Wheel well splash shields

Pinpoint Tests L: Front End Noise - Driving Straight On Smooth Roads