Subaru LEGACY 2006 Manual page 4014

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10.General Diagnostic Table
A: INSPECTION
Trouble
• Steering effort is heavy
in all ranges.
• Steering effort is heavy
at stand still.
• Steering wheel vibrates
when turning.
• Vehicle leads to one side
or the other.
• Returning force of steer-
ing wheel to center is poor.
• Steering wheel vibrates
when turning.
*
1 If the tires or wheels are wider than standard, the load to the power steering system is increased. Accordingly, in a condition,
for example before fluid warms-up, relief valve may work before reaching maximum turning angle. In this case, steering effort
may be heavy. When the measured hydraulic pressure is normal, there is no abnormal thing.
*
2 In cold weather, steering effort may be heavy due to increased flow resistance of cold fluid. After warming-up engine, turn the
steering wheel from stop to stop several times to warm-up fluid. If steering effort reduces normally, function is normal.
*
3 In cold weather or with insufficient warm-up of the engine, steering effort may be heavy due to excessive drop of idle rpm when
turning the steering wheel. In this case, start the vehicle with increasing engine speed than usual. If steering effort reduces nor-
mally, function is normal.
General Diagnostic Table
Possible cause
1. Pulley belt
• Unequal length of pulley belts
• Contact with oil or grease
• Looseness or damage of the pulley belt
• Poor uniformity of the pulley belt cross section
• Pulley belt touches to pulley bottom
• Poor revolution of pulleys (except oil pump pulley)
• Poor revolution of oil pump pulley
2. Tire and wheel
• Improper tire out of specifications
• Improper wheel out of specifications
• Tires not properly inflated
3. Fluid
• Low fluid level
• Air entry in fluid
• Dust entry in fluid
• Fluid deterioration
*
• Inadequate warm-up of fluid 2
4. Idle speed
• Lower idle speed
• Excessive drop of idle speed at start or when turning the steering
*
wheel 3
5. Measure the hydraulic pressure. <Ref. to PS-50, INSPECTION, Oil
Pump.>
6. Measure the steering wheel effort. <Ref. to PS-58, MEASUREMENT
OF STEERING EFFORT, INSPECTION, General Diagnostic Table.>
1. Fluid line
• Folded hose
• Flattened pipe
2. Tire and wheel
• Flat tire
• Mixed use of different tires
• Mixed use of different wheels
• Abnormal wear of tire
• Unequal tread remaining
• Unequal pressure of tire
3. Front alignment
• Improper or unequal caster
• Improper or unequal toe-in
• Loose suspension connections
4. Others
• Damaged joint assembly
• Unbalanced height
• Unbalanced weight
5. Measure the steering wheel effort. <Ref. to PS-58, MEASUREMENT
OF STEERING EFFORT, INSPECTION, General Diagnostic Table.>
PS-55
POWER ASSISTED SYSTEM (POWER STEERING)
*
1
*
1
Corrective action
Adjust or replace.
Replace or reinflate.
Refill, bleed air, replace or
instruct customer.
Adjust or instruct cus-
tomer.
Replace the problem
parts.
Adjust or replace.
Correct or replace.
Adjust, fix or replace.
Adjust or retighten.
Replace, adjust or instruct
customer.
Adjust or replace.