Final answer:
It's illegal to use fog lights or auxiliary lights when the weather is clear without visibility issues, or in well-lit urban areas during regular traffic conditions, to prevent dazzling other drivers.
Step-by-step explanation:
There are specific conditions where it is illegal to use fog lights or auxiliary lights on a vehicle. One such condition is when the weather is clear, and there are no visibility issues that would necessitate the use of these kinds of lights. Using fog lights during clear conditions can dazzle other drivers, which is why it is prohibited. The second condition is when you are driving in regular traffic conditions within city limits where the roads are well-lit. Fog lights can be a distraction and can reduce visibility for other drivers because of glare, especially in rearview mirrors.