Abstract: Pressure charging apparatus, which may be a turbocharger or a supercharger, for an internal combustion engine comprises a pressure supply, a wastegate, a wastegate actuator for closing and opening the wastegate in order to alter the pressure in the engine inlet, a boost control for controlling the wastegate actuator, a boost control solenoid valve, a switchover valve, electronic control units and a full throttle sensor. In operation, unit receives signals, inter alia, from the sensor to control valves to positively shut the wastegate until an overboost threshold is reached thereby minimizing boost lag during this period.

Abstract: Apparatus for controlling the electrical functions in a plurality of different locations of a vehicle comprises a plurality of electrical control units connected to a data bus (23) and distributed throughout the vehicle. All control units are identical and all are programmed to carry out all the electrical functions of the vehicle. Each unit incorporates means to detect the resistance at the point at which it is connected into the circuitry and to compare that resistance with the stored table of resistance and to select on the basis of that comparison the program for operation appropriate to the particular location in which the unit is disposed. In this way only one unit needs to be certified and units may be switched from location to location to provide a "get you home" service should one of the units fail in a particularly critical location.

Abstract: A collapsible steering column arrangement for a vehicle comprises a U-shaped deformable member connected to a fixed support for the steering column and a deforming member connected to the steering column itself. Under impact conditions caused by an accident the members move relative to one another thus allowing the steering column to collapse. This relative movement of the members enables the deforming member to contact the base of the `U` to deform the U-shaped deformable member to reduce its overall length thus absorbing the energy of the impact and allowing the column to collapse in a controlled manner. The members can be shaped and dimensioned to give the desired energy absorption characteristics.

Abstract: A differential assembly for a vehicle comprises four pinions mounted on respective identical carrier pins mounted at 90.degree. intervals in a carrier member. The pins are screwed into correspondingly screwed sockets tightened to a predetermined torque and locked in position by respective locking pins which engage undercuts formed in respective pins. Catastrophic failure due to single pin failure is thereby avoided.