Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Control Module And Hydraulic Unit Assembly Overview
Anti-lock Brake System (ABS)/Electronic Differential Lock (EDL)/Anti-Slip Regulation (ASR)/Electronic Stabilization Program (ESP), TRW
- Brake Booster
- Removing and installing, refer to BRAKE BOOSTER
- Brake Line
- Master brake cylinder/primary piston circuit to hydraulic control unit
- Identification: diameter 6.5 mm and tube fitting with longer thread M12 x 1
- Marked on hydraulic unit with HZ1
- Brake Line
- Master brake cylinder/secondary piston circuit to hydraulic unit
- Identification: diameter 6.5 mm and tube fitting with longer thread M12 x 1
- Marked on hydraulic unit with HZ2
- Brake Line
- To right front brake caliper
- Identification: diameter 5.25 mm and tube fitting with thread M 10 x 1
- Marked on hydraulic unit with VR
- Brake Line
- To left rear brake caliper
- Identification: diameter 5.25 mm and tube fitting with shorter thread M12 x 1
- Marked on hydraulic unit with HL
- Brake Line
- To right rear brake caliper
- Identification: diameter 5.25 mm and tube fitting with thread M 10 x 1
- Marked on hydraulic unit with HR
- Brake Line
- To left front brake caliper
- Identification: diameter 5.25 mm and tube fitting with shorter thread M12 x 1
- Marked on hydraulic unit with VL
- ABS Control Module -J104-
It is not possible to separate the control module and hydraulic unit.
- Removing and installing, refer to ABS CONTROL MODULE AND HYDRAULIC UNIT
- ABS Hydraulic Unit -N55-
It is not possible to separate the control module and hydraulic unit.
- Removing and installing, refer to ABS CONTROL MODULE AND HYDRAULIC UNIT
- Bracket
- Inner TORX® Bolt
- 8 Nm
- Rubber Insulation
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.