There is a high internal leakage.

Refer to Power Steering Gear and Pump Leaks .

The power steering gear valve spool is ticking/damaged.

Inspect the power steering gear.Refer to Power Steering System Test

Replace the power steering gear.Refer to Steering Gear Replacement .

The power steering pump pressure is insufficient.

Test the power steering system.Refer to Power Steering System Test

Replace the power steering pump.Refer to Power Steering Pump Replacement .

The power steering fluid level is low.

Add fluid to the power steering system.

Refer to Checking and Adding Power Steering Fluid .

Inspect the power steering system for leaks. Refer to Power Steering Gear and Pump Leaks .