Yes it’s illegal if you do not signal your intentions before maneuvers.
And yes you can get a ticket for failing to signal your intentions.
151 – Change Lanes without Signal – $109 & 2 Penalty Points
170(1) No Signal on Turn – $121 & 2 Penalty Points
More thoughts on the Illegal Not to Signal Notion
Technically, you are required to signal if there is someone to signal to. This makes sense considering the point of a turn signal is to tell other people what you are about to do and/or would like to do! (What a concept lol)
If you are the only person around and driving at 4 AM all by yourself on the road then technically you do not have to signal.
But keep in mind you are still required to signal to any type of road user that is present. That includes pedestrians & cyclists, as well as drivers. And, this includes people that you may not notice when driving at 4 AM.
I would recommend to just do it as a regular habit. It’s not difficult and safety is improved whenever others can anticipate your actions.
(2) When a vehicle is constructed or loaded in a manner that makes a signal by hand and arm not visible both to its front and rear, or a body or load extends more than 60 cm to the left of the centre of the steering wheel, a driver must give signals as provided by paragraph (1) (a) or (b), and a person must not drive the motor vehicle on a highway unless it is so equipped.
Is it illegal to Not Signal When Merging?
Yes, you are legally required to signal BEFORE merging
Merging onto a highway is technically the same maneuver as a lane change (you’re just driving faster)
Signals are important in this case to warn traffic that you’re planning a movement, especially during those instances where the on ramp and the off ramp is the same lane.
Do I have to Signal if I’m in a Turning Lane?
Legally you must signal if you’re in a turning lane. Sure, it’s obvious to you that you are going to turn, but what about pedestrians, cyclists, and vehicles facing you, especially those who aren’t familiar with the area?
Other road users may be planning movements, so it is best to signal to avoid confusion. Also remember that not everyone is a driver. Pedestrians who aren’t drivers are sometimes particularly clueless, so signals can help them for sure.