Take Bahrain Heavy Vehicle Theory Practice Questions - Bahrain Heavy Vehicle Driving Licence Theory Test (Private Transport and Special Use classes) Exam

QUESTION 1 / 25

What is the primary function of the air compressor governor in a commercial vehicle dual air brake system?

Choose one answer below.

ATo lubricate the brake drums and linings with oil mist✓BTo control when the air compressor pumps air into the storage reservoirs by managing cut-in and cut-out pressures✓CTo measure engine coolant temperature✓DTo apply the parking spring brakes automatically when changing gears✓

QUESTION 2 / 25

What are standard operating pressure ranges for air compressor cut-in and cut-out in heavy vehicle air brake systems?

Choose one answer below.

ACut-in at 40 psi and cut-out at 60 psi✓BCut-in around 100 psi and cut-out around 120 to 125 psi✓CCut-in at 150 psi and cut-out at 250 psi✓DCut-in at 10 psi and cut-out at 30 psi✓

QUESTION 3 / 25

The low air pressure warning device (buzzer and red dashboard light) on an air-braked vehicle is designed to alert the driver at what point?

Choose one answer below.

AOnly after the spring brakes have already applied themselves automatically✓BWhile enough reserve pressure still remains to bring the vehicle to a controlled stop✓COnly when the reservoirs have emptied completely✓DOnly when reservoir pressure rises above the governor cut-out setting✓

QUESTION 4 / 25

What happens automatically to a heavy vehicle's spring parking brakes if air pressure drops catastrophically below 20–45 psi?

Choose one answer below.

AThe truck accelerates to full speed✓BThe heavy mechanical coil springs overcome remaining air pressure and apply the emergency parking brakes fully✓CThe transmission shifts automatically into neutral✓DThe steering wheel locks in the straight-ahead position✓

QUESTION 5 / 25

What is 'brake lag' in commercial vehicles equipped with air brake systems?

Choose one answer below.

AThe delay caused by the driver deciding when to brake✓BThe physical time required for compressed air to travel through the airlines and chambers to actuate the brake shoes (approx. 0.4 to 0.5 seconds)✓CThe time it takes to replace worn brake pads in a workshop✓DThe delay caused by air conditioner compressors✓

QUESTION 6 / 25

Why must condensed water and oil be drained daily from manual air brake storage tanks in commercial vehicles?

Choose one answer below.

ATo reduce the vehicle gross vehicle weight by 500 kilograms✓BWater and oil sludge can cause valve corrosion, freeze in cold lines, damage rubber seals, and reduce air storage capacity✓CTo reuse the drained fluid as windshield washer solvent✓DAir tanks do not need to be drained if the vehicle is parked indoors✓

QUESTION 7 / 25

What is the purpose of the safety relief valve installed on the supply (wet) air reservoir?

Choose one answer below.

ATo release compressed air to sound the air horn✓BTo protect the system from excessive pressure buildup (typically opening around 150 psi) if the governor fails to cut out✓CTo pump air into flat tyres while driving✓DTo cool the transmission oil✓

QUESTION 8 / 25

What causes 'brake fade' on a heavy commercial vehicle descending a long slope?

Choose one answer below.

AExcess air entering the tyres from the road surface✓BExcessive heat generated by continuous friction causing brake drum expansion, lining glazing, and severe reduction in stopping friction✓CCold air flowing over the brake shoes✓DThe engine running out of diesel fuel✓

QUESTION 9 / 25

What is the proper technique for descending steep downhill grades in a heavy commercial vehicle?

Choose one answer below.

AShift into Neutral and ride the service brakes continuously down the hill✓BSelect a low gear before starting down the grade, engage engine retarders/exhaust brakes, and use intermittent snub braking when necessary✓CTurn off the engine to let the truck coast quietly✓DPump the foot brake pedal rapidly 100 times per minute✓

QUESTION 10 / 25

What is an auxiliary engine retarder (e.g., Jake Brake, exhaust brake, or hydraulic retarder) and when should it be switched off or reduced?

Choose one answer below.

AA device that sprays water on the windshield; switch off in rain✓BA supplementary braking system that uses engine compression or drivetrain resistance to slow the vehicle; switch off or reduce setting on wet, icy, or slippery roads✓CA device that increases engine turbocharger boost✓DA mechanism to lock the trailer wheels during high-speed highway cruising✓

QUESTION 11 / 25

Under Article 158 of Bahrain's Traffic Law Implementing Regulation (Decision No. 154 of 2015), what is the maximum permitted gross weight of a private-transport goods vehicle with four or more axles?

Choose one answer below.

A12 tonnes✓B40 tonnes✓C60 tonnes✓DNo maximum applies as long as the manufacturer's rating is respected✓

QUESTION 12 / 25

Under Article 158 of Bahrain's Traffic Law Implementing Regulation, what is the maximum overall length permitted for a tractor coupled to a semi-trailer?

Choose one answer below.

A12 metres✓B20 metres✓C18 metres✓D23 metres✓

QUESTION 13 / 25

What is the function of the yellow diamond-shaped push-pull knob on a heavy commercial vehicle dashboard?

Choose one answer below.

AAir horn control✓BParking brake control valve (pull to apply parking brakes, push to release)✓CEngine oil pump primer✓DDifferential cross-lock engagement✓

QUESTION 14 / 25

What is the function of the red octagonal push-pull knob on a truck tractor dashboard?

Choose one answer below.

AEmergency passenger ejection✓BTrailer air supply valve (push to supply air to trailer, pull to shut off trailer supply and set trailer emergency brakes)✓CFuel tank switch valve✓DCabin air conditioning booster✓

QUESTION 15 / 25

What is the 'slack adjuster' in an S-cam drum brake system and what is its critical safety role?

Choose one answer below.

AA device to adjust radio volume automatically with engine speed✓BA mechanical link between the brake chamber pushrod and the S-cam shaft that adjusts for brake lining wear to maintain proper pushrod stroke✓CA spring that cushions driver seat vibrations✓DA valve that regulates windscreen washer spray pressure✓

QUESTION 16 / 25

What is the danger of manual slack adjusters being out of adjustment (excessive pushrod stroke)?

Choose one answer below.

AThe truck will consume 50% more engine oil✓BThe brake chamber pushrod will reach the bottom of its travel stroke without applying adequate friction against the drum, resulting in severe braking failure✓CThe vehicle headlights will point upwards✓DThe air compressor will stop pumping air entirely✓

QUESTION 17 / 25

What does a dual air brake system mean in commercial vehicle terminology?

Choose one answer below.

AA system with two brake pedals side-by-side for the driver and passenger✓BTwo separate pneumatic circuits (Primary for rear axles, Secondary for front/steering axle) sharing a common reservoir charge but operating independently for safety✓CA truck equipped with both air brakes and bicycle rim brakes✓DA system that only works when two drivers operate the controls simultaneously✓

QUESTION 18 / 25

What is the purpose of an air dryer cartridge installed in a heavy vehicle air brake system?

Choose one answer below.

ATo warm up the passenger cabin on cold winter mornings✓BTo remove moisture, oil droplets, and contaminants from compressed air before it enters the storage reservoirs✓CTo dry wet brake pads after driving through puddles✓DTo filter engine exhaust gases✓

QUESTION 19 / 25

Why should you never use the trailer hand valve (trolley brake handle) to park a tractor-trailer combination?

Choose one answer below.

AIt causes the trailer refrigeration unit to stall✓BAir can leak down over time, causing trailer service brakes to release and allowing the unattended vehicle to roll away✓CIt discharges the tractor starter battery✓DThe hand valve can only be used when moving at speeds over 100 km/h✓

QUESTION 20 / 25

What is the function of the quick release valve in an air brake system?

Choose one answer below.

ATo disconnect the trailer from the fifth wheel instantly✓BTo exhaust air quickly from brake chambers close to the wheels when the pedal is released, preventing brake drag and delay✓CTo empty the fuel tank in an emergency✓DTo drop tyre pressures during desert driving✓

QUESTION 21 / 25

Under Article 158 of Bahrain's Traffic Law Implementing Regulation, what is the maximum permitted height of a private-transport goods vehicle measured from ground level?

Choose one answer below.

A3.0 metres, measured to the top of the cab only✓B4.5 metres, and the measurement includes the load✓C5.5 metres, excluding any load✓DThere is no statutory height limit in Bahrain✓

QUESTION 22 / 25

What is Anti-lock Braking System (ABS) malfunction lamp behavior on a commercial truck ignition startup?

Choose one answer below.

AThe lamp must stay on permanently while driving✓BThe yellow ABS lamp should illuminate upon ignition turn-on and extinguish after a few seconds if the system passes self-check✓CThe lamp should never light up under any circumstances✓DThe lamp flashes continuously in green✓

QUESTION 23 / 25

How does an Anti-lock Braking System (ABS) assist a commercial vehicle driver during emergency braking?

Choose one answer below.

AIt stops the vehicle instantly in zero meters✓BIt prevents wheels from locking up into a slide, thereby maintaining directional steering control and preventing jackknifing✓CIt automatically turns the steering wheel toward the nearest exit✓DIt releases parachute brakes behind the trailer✓

QUESTION 24 / 25

Article 68 of Bahrain's Traffic Law Implementing Regulation lists the outcomes a secured load must guarantee. Which of the following is one of them?

Choose one answer below.

AThe load must be arranged so it can be unloaded within thirty minutes✓BThe load must not obscure hand signals, indicator lights, vehicle lamps, mirrors or the registration plates✓CThe load must be covered only when the vehicle leaves the Kingdom✓DThe load must be weighed by the driver at the start of every journey✓

QUESTION 25 / 25

Why should you never depress the brake pedal when the spring parking brakes are fully applied?

Choose one answer below.

AIt will blow the vehicle horn loudly✓BIt causes 'compounding'—combining spring force with air chamber force, which can bend pushrods, rupture chambers, or crack brake drums✓CIt causes diesel fuel to spray onto the tyres✓DIt disables the power steering pump✓