Front Brake Malfunction 106 Technical Training 553 Brake Systems Technician

Front brake malfunction 106 technical training 553

This preview shows page 114 - 119 out of 184 pages.

Front Brake Malfunction 106 Technical Training
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553 Brake Systems Technician Handbook CAUTION NOTE Hydraulic Brake Booster Service and Precautions Technical Training 107 Fluid Level Check Before checking brake fluid level, turn the ignition OFF and pump the brake pedal 40 times to release pressure from the accumulator and return brake fluid to the reservoir (Note on some models the number of times the brake pedal must be pumped may vary. Refer to the repair manual for details). Fluid level should be at the maximum level mark on the reservoir. Brake Booster Bleeding Bleed the brake booster if the master cylinder is disassembled, any brake line is disconnected from the master cylinder, or the reservoir is emptied. To bleed the brake booster, turn the ignition ON and wait until the pump motor stops (30 to 40 seconds). Then turn the ignition OFF and pump the brake pedal 40 times. Brake System Bleeding Before and during brake system bleeding, check the reservoir fluid level. Turn the ignition ON and wait until the pump motor stops (30 to 40 seconds). Bleed air at each wheel, using the brake pedal to apply pressure as you would with a non-ABS brake system. The accumulator provides fluid to the rear brakes continuously. Close the bleeding screw when the fluid is free of air bubbles . Do not allow the reservoir fluid level to go below the MIN mark during bleeding. Air in the rear brake circuit will not cause the pedal to feel spongy.
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553 Brake Systems Technician Handbook Connect the Techstream to DLC3, turn the ignition ON, and access the ACTIVE TEST mode. Loosen a rear wheel cylinder bleeder plug. Select TRAC solenoids SRMF and SRMR (this activates the solenoids and forces fluid to the rear wheel cylinders). To protect the solenoids, Techstream automatically stops the active test after 2 seconds. You may need to repeat the active test several times to remove all the air from the fluid lines. Do not depress the brake pedal during the solenoid active test. CAUTION Master Cylinder Solenoid Bleeding 108 Technical Training
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553 Brake Systems Technician Handbook Section 8 Topics Technical Training 109 This section covers hydraulic brake force distribution, including: 1. Proportioning and bypass valves 2. Double proportioning valves 3. Load sensing proportioning valves (LSPV) 4. Load sensing proportioning and bypass valves (LSPBV) 5. Testing and adjustment
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553 Brake Systems Technician Handbook Hydraulic Control 110 Technical Training As dynamic conditions change during braking, a weight transfer occurs that shifts some of the load from the rear toward the front. This effectively reduces the braking force that can be applied through the rear wheels. Therefore a front to rear brake force distribution is made to optimize braking performance. At lower vehicle speeds, fluid pressure is nearly equal at both front and rear brake assemblies as the coefficient of friction is the same front to rear; however, as vehicle speed or brake demand increases, pressure to the rear brakes must be reduced to prevent the wheels from locking.
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  • Fall '08
  • Huie,B
  • Brake, Disc brake, Drum brake, Vehicle braking technologies, Brake Systems, disc brakes

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