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Home >> Lincoln >> 2004 >> Aviator RWD >> Repair and Diagnosis >> Steering >> Power Steering >> Steering System >> Diagnosis And Testing >> Steering System >> Symptom Chart
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Symptom Chart

SYMPTOM CHART

Condition Possible Sources Action
  • No communication with the variable assist power steering (VAPS) module
  • Circuitry.
  • VAPS module.
  • Unable to enter self-test
  • Variable assist power steering (VAPS) module.
  • Diagnostic tool.
  • Hard steering or lack of assist (no DTCs present)
  • Seized lower steering column shaft U-joints.
  • Damaged, fractured steering column bearing(s).
  • Power steering pump.
  • Suspension components.
  • Steering gear internal leakage.
  • Steering system noise
  • Low fluid level.
  • Fluid aeration.
  • Steering gear.
  • Power steering pump.
  • Loose or damaged steering linkage.
  • Loose or damaged suspension component(s).
  • Steering column.
  • Steering column boot bearing.
  • Intermediate shaft.
  • Loose dash boot seal.
  • Steering is very difficult/very easy
  • Seized intermediate shaft U-joints.
  • Damaged, fractured steering column bearing(s).
  • Steering gear.
  • Power steering pump.
  • Power steering hoses.
  • Binding dash boot seal.
  • Excessive steering wheel play
  • Steering gear.
  • Steering column.
  • Steering column intermediate shaft.
  • Steering linkage.
  • Ball joints.
  • Steering system drift/pull/wander
  • Tire pressure.
  • Unevenly loaded vehicle.
  • Wheel alignment.
  • Steering gear.
  • Steering column intermediate shaft.
  • Frame alignment.
  • ADJUST tire pressure as necessary.
  • CORRECT the vehicle loading as necessary.
  • GO to PINPOINT TEST H .
  • Feedback
  • Loose, worn or damaged tie-rod.
  • Loose, worn or damaged tie-rod ends.
  • Loose or damaged steering gear insulators or bolts.
  • TIGHTEN the bolts or INSTALL new steering gear insulators as necessary.
  • Loose lower steering column shaft U-joint or pinch bolts.
  • TIGHTEN or INSTALL new lower steering column shaft and bolts as necessary. REFER to STEERING COLUMN .
  • Loose suspension bushings, fasteners, ball joints or strut bearing plate (if applicable).
  • Worn or damaged steering column bearing(s).
  • Poor returnability/sticky steering
  • Binding lower steering column shaft U-joints.
  • Loose, worn or damaged front wheel knuckle tie-rod.
  • Loose, worn or damaged tie-rod ends.
  • Suspension components.
  • Binding steering column bearing(s).
  • Binding dash boot seal.
  • INSTALL new steering column bearing(s) or dash boot seal as necessary. REFER to STEERING COLUMN .
  • Shimmy
  • Loose, worn or damaged tie-rod end.
  • Loose, worn or damaged tie-rod.
  • Suspension components.