Control Module, Removing And Installing Separately: Removing
-- On vehicles with a coded radio, note the code. Retrieve it if necessary.
-- Disconnect the battery. Refer to BATTERY, DISCONNECTING AND CONNECTING .
-- Remove the hose -1- and loosen the hose clamps -arrows- to remove the air guide pipe (not on all engines).
On Vehicles with Diesel Engine
-- Remove the fuel filter -arrows- and move it to the side, but do not remove the fuel lines.
-- Disconnect the air suspension connector, remove the bolts -arrows- and then remove the fuel filter bracket.
Continuation For All Vehicles
-- Remove the bolts -arrows- from the coolant expansion tank -1-.
-- Push the coolant expansion tank -1- in direction of -arrow- from the mount.
-- Set the coolant reservoir -1- aside.
Do not remove the coolant hoses.
-- Thoroughly clean the control module, hydraulic unit and the surrounding area.
-- Vacuum the control module, hydraulic unit and the broader area with a vacuum cleaner so that no dirt and moisture can enter the system.
-- Release the connector from the control module -arrow 1- and remove -arrow 2-.
-- Remove the control module -2- and remove it from the hydraulic unit -3- without tilting it.
The illustration shows the coolant expansion tank -1- removed and lying on its side.
-- Check the valves for damage.
-- Clean the sealing surface.
Do not use aggressive cleaning agents (use cleaning agent enclosed).
Check the sealing surface for damage (visual check).
No moisture or dirt particles must get into the control module.
Replace the hydraulic unit if the sealing surface or contact tags are damaged.
Excessive shaking (for example, dropping, impact) may destroy the control module. The control module must then no longer be used.