ABS control units manufactured before around 1996 are mostly located inside of vehicle interior. Since 1996 you find them at the hydraulic manifold in the engine compartment.
Yes, in most cases the device can be removed without hydraulic system. If you do not detach hydraulic lines no hydraulic fluid will leak. In vehicles manufactured in 1995 and later the control unit is attached to the ABS hydraulic manifold with 4 to 6 screws. You will also find 1 or 2 plug connexions. After removal of the plugs and screws you can pull the ABS control unit from the hydraulic manifold. To manage this a 4 cm distance between the unit and parts behind is required.
Follow instructions of the manufacturer when exchanging the control unit.
An engine control unit can be located in the engine compartment and in the vehicle interior as well.
Opel vehicles 1998 and later: in most cases on the cylinder head.
Mercedes vehicles: in most cases under a polymer cover in the engine compartment at the kerbside near the bulkhead.
VW T4: In the engine compartment on the driver side next to the battery
Old Suzuki vehicles:
In the vehicle interior under the glove compartment (Samurai, SJ413)
In the vehicle interior near the fuse box in the footwell on the driver side (Vitara)
Old Mitsubishi vehicles:
In the footwell on the driver side under the driver seat or centre console.
Volvo 940, 945, 740, 745:
In the vehicle interior on the kerbside's footwell.
Volvo 850, V70:
In the engine compartment on the kerbside in a plastic box.
last update: 19.5.2019