Brake system

Chapter overview

• Technical data
  1
• 1 Safety information
  1
• 1.1 Safety precautions when working on vehicles with a start/stop system
  1
• 1.3 Safety precautions when working in the vicinity of high-voltage components
  1
• 1.4 Safety precautions when working on high-voltage system
  2
• 2 Identification
  3
• 2.1 Allocation of PR number - brakes
  3
• 3 Repair notes
  5
• 3.1 Rules for cleanliness
  5
• 3.2 General repair instructions
  5
• 3.3 Contact corrosion
  5
• 4 Technical data
  6
• 4.1 Technical data for brakes
  6
• 5 Brake test
  8
• 5.1 General information
  8
• 5.2 Checking vehicles with all-wheel drive
  8
• 5.3 Checking parking brake
  8
• Anti-lock brake system
  10
• 1 General information
  10
• 1.1 Repair instructions for ABS
  10
• 2 Overview of fitting locations
  13
• 2.1 Overview of fitting locations - ABS/ESP
  13
• 3 Control unit and hydraulic unit
  15
• 3.1 Assembly overview - control unit and hydraulic unit
  15
• 3.2 Removing and installing ABS control unit J104 and ABS hydraulic unit N55
  19
• 3.3 Separating control unit from hydraulic unit
  24
• 3.4 Fitting control unit to hydraulic unit
  25
• 3.5 Connecting brake lines to hydraulic unit
  27
• 4 Sensors
  28
• 4.1 Assembly overview - speed sensor on front axle
  28
• 4.2 Assembly overview - speed sensor on rear axle
  29
• 4.3 Removing and installing speed sensors on front axle G45 / G47
  29
• 4.4 Removing and installing speed sensors on rear axle G44 / G46
  30
• 4.5 Checking ABS sensor ring
  30
• 4.6 Removing and installing ESP sensor unit G419
  31
• Brakes - mechanism
  32
• 1 Front brake
  32
• 1.1 Assembly overview - front brake
  32
• 1.2 Removing and installing brake pads
  35
• 1.3 Removing and installing brake caliper
  38
• 1.4 Removing and installing brake disc
  43
• 1.5 Removing and installing brake splash plate
  44
• 1.6 Removing and installing pad wear indicator wire
  45
• 2 Rear brake
  47
• 2.1 Assembly overview - rear brakes
  47
• 2.2 Removing and installing brake pads
  49
• 2.3 Removing and installing brake caliper with brake carrier
  53
• 2.4 Removing and installing brake caliper
  56
• 2.5 Removing and installing brake carrier
  59
• 2.6 Removing and installing brake disc
  60
• 2.7 Removing and installing brake splash plate
  61
• 2.8 Removing and installing pad wear indicator wire
  62
• 3 Parking brake
  64
• 3.1 Assembly overview - parking brake
  64
• 3.2 Removing and installing parking brake motor V282 / V283
  65
• 3.3 Releasing parking brake manually
  66
• 4 Brake pedal
  68
• 4.1 Assembly overview - brake pedal
  68
• 4.2 Removing and installing mounting bracket
  69
• 4.3 Separating brake pedal from brake servo
  72
• 4.4 Connecting brake pedal to brake servo
  73
• 4.5 Removing and installing brake pedal
  73
• Brakes - hydraulics
  76
• 1 Front brake caliper
  76
• 1.1 Assembly overview – front brake caliper
  76
• 1.2 Removing and installing brake caliper piston
  76
• 2 Rear brake caliper
  80
• 2.1 Assembly overview – rear brake caliper
  80
• 2.2 Removing and installing brake caliper piston
  81
• 3 Brake servo and brake master cylinder
  85
• 3.1 Assembly overview - brake servo/brake master cylinder
  85
• 3.2 Removing and installing brake light switch
  90
• 3.3 Removing and installing brake servo
  92
• 3.4 Removing and installing brake master cylinder
  97
• 3.5 Removing and installing brake fluid reservoir
  101
• 3.6 Removing and installing brake fluid level warning contact F34
  103
• 3.7 Removing and installing brake system pressure accumulator VX70
  104
• 3.8 Note regarding operating pin
  106
• 4 Vacuum system
  107
• 4.1 Assembly overview - vacuum pump
  107
• 4.2 Checking non-return valve
  111
• 4.3 Removing and installing non-return valve
  111
• 4.4 Removing and installing brake servo pressure sensor
  114
• 4.5 Checking vacuum system
  115
• 5 Brake lines
  120
• 5.1 Repairing brake lines
  120
• 6 Hydraulic system
  124
• 6.1 General notes on brake fluid
  124
• 6.2 Bleeding hydraulic system
  124
• 6.3 Pre-bleeding brake system pressure accumulator VX70
  133
• 6.4 Testing for leaks
  134