A couple interesting things that I found while searching the HTA
Attachment that affects lamps prohibited
(7) No person shall drive upon a highway a motor vehicle if either or both of the lamps that are required on the front of the vehicle by subsections (1), (2) and (3),
(a) are coated or covered with a coloured material; or
(b) have been modified by the attachment to the lamps or the motor vehicle of any device that reduces the effective area of the lenses or the intensity of the beam of the lamps. 2002, c. 18, Sched. P, s. 19 (1).
Basically you can't coat your headlights with anything, tinting, or painting. Also according to part B, the GTS headlight covers are illegal as well.
Strength of front lamps
(9) No motor vehicle shall carry on the front thereof more than four lighted lamps that project a beam having an intensity of over 300 candela. R.S.O. 1990, c. H.8, s. 62 (9).
Can't drive with more than 4 headlights, and for those running projectors, your projectors can't excced 300 candela
Vehicles of firefighters
(16) A firefighter, within the meaning of subsection 1 (1) of the Fire Protection and Prevention Act, 1997, may carry on or in his or her vehicle a lamp that produces intermittent flashes of green light and may operate the light if the motor vehicle is proceeding to a fire or other emergency. 1997, c. 4, s. 81.
(16.1) No person other than a person described in subsection (16) shall operate a lamp that produces intermittent flashes of green light. 1994, c. 35, s. 1.
Mark, I don't think you are a firefighter.............LOL
Flashing blue light on snow-removal equipment
(31) No person shall, while operating a road service vehicle on a highway, plow, salt or de-ice the highway or apply chemicals or abrasives to the highway for snow or ice control unless the road service vehicle is equipped with a lamp producing intermittent flashes of blue light visible for a distance of 150 metres from all directions. 1996, c. 33, s. 11.
Restriction on use of flashing blue light
(32) No person shall operate a lamp that produces intermittent flashes of blue light on a highway except in the circumstances described in subsection (31). 1996, c. 33, s. 11.
I believe that everybody knows this one, no flashing blue lights, unless you are a snowplow, but then some of the mod'd cars out there can be considered a snow plow.
62. (1) When on a highway at any time from one-half hour before sunset to one-half hour after sunrise and at any other time when, due to insufficient light or unfavourable atmospheric conditions, persons and vehicles on the highway are not clearly discernible at a distance of 150 metres or less, every motor vehicle other than a motorcycle shall carry three lighted lamps in a conspicuous position, one on each side of the front of the vehicle which shall display a white or amber light only, and one on the rear of the vehicle which shall display a red light only. R.S.O. 1990, c. H.8, s. 62 (1).
From what I read, basically with this one, ALL cars must only have white and amber visable from the front of the car, this is where I think the cops can get you for underglow lights............unless they are white or amber, but those colours are gay
But here is the grey area,
shall display a white or amber light only
is a reflection off the surface of the road considered displaying? It is a misleading description in the HTA