Document RaJeNqja8Kvw0QXpLBer9KN6n

LESSON ONE-MODULE 1 BRAKE SYSTEM DIAGNOSIS AND TESTING Hydro-Boost System Inspection (Continued) Hydro-boost Unit on Bench Accumulator Test: With the engine ON, turn the steering wheel from stop-to-stop, then return the wheel to the center position. With the engine OFF, pump the brake pedal. There should be power assist for 2 or 3 brake applications. Repeat the first step. Turn the engine OFF and wait 1 hour. Repeat step 2. There should be power assist for 1 or 2 brake applica tions. If the accumulator test fails, replace the hydro-boost unit. Hydro-Boost Air Bleeding If a hydro-boost or power steering component is removed for service, the power steering hydraulic system must be bled of air. Air can also enter the system if the fluid level drops below the minimum specified level in the reservoir. When checking power steering fluid, look for signs of air. Aerated fluid looks milky. Fill the power steering pump reservoir to the maximum specified level. Allow to settle with the engine off for 5 minutes. Turn the engine ON and allow to idle for 1 minute. Turn the engine OFF and check the fluid level and fill if necessary. Repeat the first 2 steps until the fluid stabilizes at the full mark. Raise the front wheels off the ground and turn the steering wheel from stop-to-stop with the engine OFF. Check the fluid level and fill if necessary. Lower the vehicle and turn the engine ON. Apply the brakes and turn the steering wheel from stop-to-stop. Turn the engine OFF and pump the brake pedal 3-5 times. Check the fluid level. If the fluid appears to be foaming, allow the vehicle to settle with the engine off for 10 minutes. Repeat this procedure until the fluid in the reservoir is clear (no foaming). If the bleeding procedure fails to remove the air from the system, there may be a problem in the power steering pump. Refer to the Workshop Manual for steering system testing procedures. 8 September, 2005 Brake System Diagnosis and Repair