warning sign

Dip ahead

Thai road sign ต.37 — Dip ahead. Meaning: A dip in the road surface lies 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: ป้ายเตือนทางเป็นแอ่ง

Independent English reference · Source: Department of Highways · Sign ต.37

Road response

On the road

Driver action

What should you do?

Reduce speed before reaching it to maintain control of the vehicle.

Exam-style scenario

Read the situation

A single low dip lies beyond the sign and may be difficult to see from your current position.

Best response: Slow before the concealed dip so the vehicle remains controlled as the road drops and rises once.

Sign comparison

Don’t confuse it

Key difference

The line drops once and rises again for a single dip; the uneven-road symbol shows multiple surface changes.

Put sign knowledge into practice.

Answer exam-style questions about road signs, traffic lights, and lane markings in clear English.

Mascot holding a blank circular road sign with a red border.