Control Module and Hydraulic Unit, Removing
Control Module and Hydraulic Unit, Removing
Special tools, testers and auxiliary items required
• Brake Pedal Actuator (V.A.G 1869/2)
Plug (1H0 698 311 A)
After separating the control module from the hydraulic unit, always install transport protection on the hydraulic unit for the valve domes.
Warranties will not be granted for hydraulic units without transport protection.
1 Transport protection for valve domes (foam)
2 Sealing plug M 10
3 Sealing plug M 12
Removing
Component location:
The control module is bolted to the hydraulic unit and is located at right in the engine compartment.
Do not bend the brake lines near the hydraulic unit.
- Read and note the present control module coding.
- Disconnect the battery.
- Remove engine cover.
Additional work on the following engines:
Diesel engines without and with a particulate filter:
- Remove the plenum chamber cover.
- Remove the plenum chamber bulkhead.
Diesel engines with particulate filter:
- Disconnect the connector for the Exhaust Gas Temperature (EGT) Sensor 4 (G648) - 2 - and Heated Oxygen Sensor (HO2S) (G39) - 3 -.
- Unclip the Exhaust Gas Temperature (EGT) Sensor 4 (G648) and Heated Oxygen Sensor (HO2S) (G39) cables from the brackets on the plenum chamber and engine.
- Disconnect the connector on the Exhaust Pressure Sensor 1 (G450).
- Remove engine cover.
- Remove the particulate filter bracket bolt - 1 -.
- Raise vehicle.
- Loosen and remove the turbocharger/particulate filter clamp - 1 -.
• The illustration shows the clamp bolt - 1 - from underneath. In some cases, this can be installed from the top.
- Remove exhaust system bracket from subframe- arrows -.
- Remove the bolts - 1 - and remove the drive axle cover - 2 -.
- Disconnect the right drive axle from the flange, lay it down and secure it.
- Loosen the double clamp on the exhaust pipe and push it toward the rear.
- Remove the nuts - 1 - and lower the particulate filter.
- Remove the nuts - 2 - and remove the particulate filter bracket - 3 -.
- Lower the particulate filter just enough so that it touches the steering gear.
• While lowering the particulate filter, pay close attention to the cable, the Exhaust Gas Temperature (EGT) Sensor 4 (G648) and the Heated Oxygen Sensor (HO2S) (G39) to prevent damage.
- Lower vehicle.
Continuation for all vehicles
- Remove the nuts - 1 - and remove the heat shield - 2 - if equipped.
- Release and remove connector from control module in - direction of arrow -.
- Install (V.A.G 1869/2).
- Attach bleeder hose of bleeder bottles to left-front and left-rear brake caliper bleeder valves and open bleeder valves.
- Operate brake pedal using (V.A.G 1869/2) at least 60 mm.
- Close left front and left rear bleeder valves.
- Do not remove (V.A.G 1869/2).
- Place sufficient lint-free cloths under the control module and hydraulic unit.
Make sure that brake fluid does not come in contact with the terminals.
- First, mark both brake lines from master cylinder - A and B - and remove from the hydraulic unit.
- Seal brake lines and threaded holes with Sealing Plugs (1H0 698 311 A).
- Mark brake lines (brake caliper) - 1 - to - 4 - and remove.
- Seal brake lines and threaded holes with Sealing Plugs (1H0 698 311 A).
- Remove the hex bolt form the bracket - arrow -.
- Remove the hydraulic unit, the control module and the side retainer in - direction of arrow - from the bracket rubber insulation and turn it on its head.
- Remove the retainer from the hydraulic unit in the engine compartment.
- Remove the hydraulic unit and the control module.