9.2 Traffic Lights, Arrows and Lane Discipline

9.2 Traffic Lights, Arrows and Lane Discipline

Quick Summary / Key Rule: Traffic lights, arrows and lane rules make up roughly one question in twelve in the published pool, and virtually all of them are Road User Handbook material. The rules are simple; the traps come from heavy-vehicle length. A truck that "just fits" through on a yellow will still be in the intersection when the light goes red.

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The Signal Sequence and What Each Colour Requires

The two rules a long vehicle gets wrong

1. Do not enter an intersection you cannot clear. If the road beyond is choked with vehicles travelling in the same direction, you must wait until there is room for your vehicle on the far side before you enter, even on a green light. This applies to a green light for going straight ahead and to a green light for turning left. In a 19-metre articulated vehicle you must judge the far-side gap against your whole combination, not against the cab.
2. A green light is not a right of way over pedestrians. A driver turning left or right must give way to pedestrians crossing the road being entered.

Red arrow with a "Left turn on red permitted after stopping" sign

Where this sign is displayed at an intersection with traffic lights, on a red light you must first stop, then turn left only if it is safe to do so. The stop is not optional and the give-way obligation is absolute.

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Lane Discipline

Keeping left

On a multi-lane road with a speed limit of more than 80 km/h, you must drive in the left lane unless you are overtaking. The same rule is signposted on many two-lane freeways. For a heavy vehicle this is reinforced by two extra rules:

• A truck over 4.5 tonnes GVM must move into a lane marked with a trucks lane sign, and must stay there at all times until a sign indicates the end of the restriction.
• Only vehicles with a GVM greater than 4.5 tonnes may use a lane marked with a trucks lane sign — it is not a general slow-vehicle lane.

Bus lanes and bus-only lanes

Bus lanes and bus-only lanes are marked by signs or by lane markings. They may be used by public buses constructed principally to carry people, equipped to seat more than eight adults including the driver, and used to carry passengers for hire or reward or in the course of trade or business. A freight truck is not entitled to use a bus lane.

The B signal

Bus-only lanes at signalised intersections often carry a separate "B" signal. If you are driving a bus in a bus-only lane and you come to a B signal that is showing, you go through the intersection as you would on a normal green signal — the B signal is the bus equivalent of the green, released early to give buses a head start.

Priority for buses

In a built-up area, other drivers should give way to a bus displaying a give way sign when the bus is in front of them and is about to enter or proceed in the line of traffic. The bus driver is still required to obey the road rules when entering the traffic — the sign creates a courtesy priority, not an unconditional right of way. Buses cannot park at bus stops, but may wait at one before starting a regular passenger service.

Turning from the correct lane

• Right turns must be made from the far right-hand lane, or from any other lane that has an arrow marked on the roadway permitting a right turn.
• Where you turn right from one of two right-turn-only lanes, you still indicate right for the whole manoeuvre.
• A long vehicle exception matters here: you may make a turn from the lane next to the left-hand lane when you are driving a vehicle over 7.5 metres long, because the vehicle physically cannot complete the turn from the kerb lane.

Lines on the road

• Double unbroken dividing lines: you may cross them to enter or leave a driveway or property, if it is safe to do so. You may not cross them to overtake.
• Unbroken lane lines: crossing one to change lanes is an offence, and it is one of the specific examples of negligent driving in the official pool.
• Changing lanes is permitted only when it is safe to do so, and you must signal.

Merging

• Where two lanes merge into one, the vehicle that has to cross a lane line gives way.
• Entering a motorway, watch for a gap and increase your speed to merge safely with the traffic already on the motorway. Merging slowly from an on-ramp in a heavy vehicle forces the through traffic to brake and is a common cause of freeway crashes.

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Emergency Vehicles and Trams

• If you hear a siren, take whatever action is safely necessary to make way for the emergency vehicle — generally move to the left and let it pass.
• At an intersection where a light rail vehicle is about to enter, wait until the intersection is clear.
• Where police or a traffic controller are directing traffic, always follow their instructions, even if that contradicts the signals or signs.

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Common Exam Traps

• ⚠️ "The light is green so I can enter." — Only if there is room for your whole vehicle on the far side.
• ⚠️ "It's 3 am and the road is empty, so I can turn on the red arrow." — No. A red arrow prohibits the turn regardless of traffic.
• ⚠️ "Yellow means speed up to clear." — No. Yellow means stop, unless stopping would require sudden braking.
• ⚠️ "A truck can use a bus lane if it is empty." — No. Bus lanes are for public buses as defined above.
• ⚠️ "I can cross double unbroken lines to get around a slow vehicle." — No. The only permitted crossing is to enter or leave a driveway or property, safely.