Theory test for vehicle combinations – class CE

Basic knowledge of how the trailer is built, its couplings and daily checks of the vehicle combination's equipment.

• Trailer types: full trailer, rigid-drawbar trailer, semi-trailer and dolly
• Couplings: pin coupling, kingpin and fifth wheel, locking and securing, D-value and U-value
• The supply connections: air hoses, lighting connector and ABS/EBS cable
• Trailer brakes: automatic braking if the connection breaks, function check and air dryer
• Lights, reflectors, contour marking and mirrors when driving with a trailer
• Daily checks: coupling, tyres, wheels, lights, brakes and load
• Winter tyres, studded tyres, snow chains and periodic inspection of the trailer
• Coupling and uncoupling: sequence, checks and safe parking
• Speed limit, stabiliser bar and entitlement to drive a vehicle combination

How the vehicle combination behaves when driving, turning, reversing and on hills, and how the driver adapts technique and speed to stay in control.

• Turning and tracking — the trailer cuts the inside of the bend, the rear overhang swings out, the tracking requirement
• Visibility and blind spots — using the mirrors, blind spots along the side and behind the vehicle combination
• Loss of grip, risk of rollover and speed in bends — crosswind, liquid loads, empty and laden vehicle combinations
• Jackknifing and trailer swing — why an empty vehicle combination is vulnerable, and driving off the edge of the tarmac
• Driving downhill — speed and gear before the hill, engine brake and retarder
• Driving uphill — choice of gear, moving off and slippery conditions
• Reversing — semi-trailer and full trailer, a helper, and straightening the vehicle combination
• Winter driving and visibility — snow chain requirements, aquaplaning, fog, tunnels and use of lights
• Overtaking, meeting and interacting with others — and when the vehicle combination should not be driven at all

How much load a vehicle combination can carry, read from the registration document and the road list, and how the load is placed, secured and marked.

• Payload: permitted total weight − kerb weight with driver; the kerb weight counts the driver as 75 kg, but at a check the actual weight applies
• The lowest limit applies: the registration documents (total weight, permitted combination weight, permitted trailer weight), axle load and bogie load, vehicle weight and combination weight by road class and minimum distance
• Road list and road class (Bk10, BkT8, Bk8, Bk6), winter axle load, spring thaw, timber vehicle combinations and modular vehicle combinations over 50 tonnes
• Truck with full trailer and rigid-drawbar trailer, tractor unit with semi-trailer: fifth-wheel load, coupling load and the 1.5 rule for the trailer's weight
• Coupling forces: D-value, U-value and calculation under § 4-6
• Load placement (at least 20% of the weight on the steered wheels) and load securing: forces, friction, direct lashing and top-over lashing, and the transport operator's duty to document
• Maximum width and length, indivisible loads, and marking of loads that stick out
• Overloading: the driver's responsibility and the consequences

How the braking systems on the tractor unit and the trailer work together, and how the driver handles braking to avoid jackknifing, snaking and rollover.

• Air brake: two circuits, working pressure and warning lights
• ABS, EBS, ESC and driver assistance systems — function, warning lights and limitations
• Load-sensing brake force regulation — empty and laden vehicle combinations
• Braking on a long downhill — engine brake, retarder and brake fade
• Jackknifing and trailer swing — an overbraked axle and the weight ratio between the vehicle and the trailer
• Snaking — causes and correction
• Brake test, breakaway brake and the trailer's parking brake
• Stopping distance — reaction distance, speed and road conditions
• Winter tyres on the trailer

The particular features of semi-trailers, modular vehicle combinations and other long and heavy vehicle combinations, and the rules for where they may be driven.

• Semi-trailer: fifth wheel, load on the tractor unit, reversing and jackknifing
• Modular vehicle combinations: permitted types, requirements for the combination, road lists, 60 tonnes and winter restrictions
• 24 m vehicle combinations and timber vehicle combinations: where they may be driven, height, projecting loads and return loads
• Road classes and road lists: axle load, total weight, length and frost-thaw restrictions
• Special transport: dispensation and escort vehicles
• Bodies and special equipment: container chassis, tipper, refrigerated body, car transporter and dangerous goods
• Safety course on a track: when it must be taken, and what you should experience

Planning, interacting with others and defensive driving in traffic with a vehicle combination, and understanding risk from the safety course on the road.

• Trip planning: route, rest time, weather, road conditions and traffic reports
• Signs that restrict vehicle combinations: weight, axle load, length, overtaking and heavy-vehicle lanes
• Following distance, overview, blind spots and reading the traffic far ahead
• Interacting with others: letting others pass, meeting on narrow roads and meeting vehicles that are overtaking
• The vehicle combination's length in traffic: turning, level crossings and queues
• Winter driving and snow chains for vehicle combinations
• Fatigue, health and driver assistance systems
• Safety course on the road and assessing your own driving

Rules that apply to both trucks and vehicle combinations, and that are part of the theory test for class C and CE.

• Give way and level crossings
• Signs for heavy vehicles: weight, length, height, width and overtaking
• Speed for heavy vehicles
• Driving and rest times and the tachograph
• Accidents, first aid and securing the accident scene
• Tunnels and winter driving
• Responsibility, sobriety and documentation