prohibition sign
No 3-wheeled motor vehicles
Thai road sign บ.18 — No 3-wheeled motor vehicles. Meaning: 3-wheeled motor vehicles are prohibited from entering or travelling on the road ahead. Learner-manual coverage: this identity is shown in the current DLT car-driver learner manual. Inclusion does not mean it appears in every theory test.
Thai name: ป้ายห้ามรถยนต์สามล้อ
Independent English reference · Source: Department of Highways · Sign บ.18
Road response
On the road
Driver action
What should you do?
3-wheeled motor vehicles are prohibited from entering or travelling on the road ahead. Drivers of such vehicles must not pass this sign.
Exam-style scenario
Read the situation
A motorised three-wheeler approaches a road entrance displaying this vehicle-class restriction.
Best response: Turn the motorised three-wheeler away from this entrance and use a permitted road.
Sign comparison
Don’t confuse it
This sign
No 3-wheeled motor vehicles
Compare with
No tricycle
Key difference
The depicted three-wheeler is motorised; the tricycle sign represents the non-motorised pedal vehicle instead.
Put sign knowledge into practice.
Answer exam-style questions about road signs, traffic lights, and lane markings in clear English.
