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Home >> Audi >> 2021 >> S4 Premium Plus >> Repair and Diagnosis (Single Page) >> Brakes >> Traction Control >> Antilock Brake System (1 Of 2) >> 45 Antilock Brake System >> Control Module And Hydraulic Unit >> Overview - Control Module And Hydraulic Unit
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Overview - Control Module And Hydraulic Unit

NOTE:

If the ABS Control Module -J104- is faulty, it can be replaced separately.

If the ABS Hydraulic Unit -N55- is faulty, it must be replaced together with the ABS Control Module -J104-.

Control Module and Hydraulic Unit

Fig 1: Exploded View Of Control Module And Hydraulic Unit
GWWA45-10202Courtesy of AUDI OF AMERICA, LLC
  1. Nut
    • 3.8 Nm
  2. Bracket
  3. Nut
    • 3.8 Nm
  4. Rubber Bushing
  5. Mounting Bracket
  6. Bolt
    • Tighten in two steps alternating from side to side.
    • Step 1: 1 to 1.5 Nm (to install the seal)
    • Step 2: 2.5 Nm
  7. ABS Control Module -J104-
    NOTE:

    The transverse and longitudinal acceleration sensors are installed in the ABS Control Module -J104-. The sensors cannot be replaced.

    If the ABS Control Module -J104- is faulty, it can be replaced separately.

    If the ABS Hydraulic Unit -N55- is faulty, it must be replaced together with the ABS Control Module -J104-.

  8. ABS Hydraulic Unit -N55-
    NOTE:

    If the ABS Control Module -J104- is faulty, it can be replaced separately.

    If the ABS Hydraulic Unit -N55- is faulty, it must be replaced together with the ABS Control Module -J104-.

  9. Brake Line
    • 14 Nm
    • To the brake caliper
  10. Brake Line
    • 14 Nm
    • From brake master cylinder to the hydraulic unit
  11. Bolt
    • 25 Nm
  12. Bolt
    • 3.8 Nm

ABS Control Module -J104-

Fig 2: Identifying Pressure Sensor Contact, Pressure Sensor, Seal, Valve Bodies And Pump Motor Contact
GWWA45-10122Courtesy of AUDI OF AMERICA, LLC
  1. Pressure Sensor Contact
    • Do not touch the contacts
    • The illustration depends on the model
  2. Pressure Sensor
    • Must not be changed or damaged
    • Cannot be replaced
    • The illustration depends on the model
  3. Seal
    • Do not remove or lift
    • Cannot be replaced separately
  4. Valve Body
    • Must not be damaged
    • Do not use any tools
  5. Pump Motor Contact
    • Must not be damaged