Isn’t there some law against people leaving their headlights on high beam or these new blue lights that blind oncoming traffic? – Marianne in Belleville, Ont.
Failure to dim your lights is indeed a no-no, but I suspect you are talking about the growing preponderance of a new generation of headlights and the resultant cheap copy-cats.
From 1940 until 1978, seven-inch round sealed beam headlights were the only ones that met U.S. federal regulations. They used a tungsten bulb and produced a fairly yellowish light. In the early 1960s, rectangular sealed beam lights were permitted and, at about that time, halogen units were also permitted. These used a tungsten filament and halogen gas to produce a brighter and whiter light. Then, in 1983, the regulations were changed to more closely reflect those in the rest of the world and headlights with replaceable bulbs were permitted.
These bulbs were commonly halogen and this was the start of the problem you have identified – these bulbs are often replaced with aftermarket ones that may or may not meet regulations.
Headlights are precisely crafted pieces. In most, the bulb is aimed to the rear, where it is bounced off a reflector, where it is focused and “reflected” forward, where it is shaped and aimed by the lens as it passes through. Another form of headlight is a projector beam unit where the light is aimed directly forward with the aim determined by movement of the lens itself. In either case, it has become common practice to replace the standard bulb with higher-power unit, blue in colour.
If the bulb is incorrectly installed or not built to the precise tolerances required by Department of Transport standards, even the slightest difference can result in a miss-aimed light.
At the start of the 1990s, high-intensity discharge or HID lights started to appear on high-end vehicles where the significantly greater costs could be buried. Also called Xenon (high beam only) or Bi-Xenon (both high and low beam), these produce a brighter, whiter light while using much less energy than the halogen bulb.
They produce light by creating an electric arc between two electrodes instead of a burning element. This light is then focused directed by a moving shield that aims the light. This shield is powered by a small electric motor.
Regulations in most parts of the world require vehicles equipped with HID lights to also be equipped with cleaning and self-levelling systems, the former a separate high-pressure windshield-washer-type spray to clear dirt or other material off the lens that may reflect or redirect the light. The self-levelling system is meant to keep the light properly aimed regardless of vehicle position. No such regulations exist here and vehicles without the self-levelling system or those with aftermarket replacement systems can be blinding when weight is placed in the trunk or cargo compartment, causing the rear of the vehicle to drop and the front – and thus the headlights – to rise.
Compounding the problem is the vast popularity of pickups and SUVs with headlights that are much further off the road and thus shining directly into the windshield, mirrors or rear window of lower vehicles.
Finally, some people try to use HID bulbs in headlight units not designed for them, creating extreme levels of glare. Yes, there are laws against this – but it is going to take a pretty focused law enforcement official to get to the bottom of it.
Tire wear
My husband pointed out one of your columns to me a while back wherein you said you did not wish to get involved in a marital dispute. Wise move! But, having said that, I’d like your opinion on one we are having. The man in my life changes our tires every fall and winter, snow tires for summer tires, etc. I happened to notice the tires he took off last fall in the garage and to me they look worn out. I mentioned this and he said they were not. How can you tell? – Lana
You need to look closely at the tires. Tires are considered unsafe or worn out when one or more of the grooves in the tread reaches 2/32nds of an inch or less. New tires commonly have a tread depth of 8-10/32nds.
Tire makers build bars in the tread that run from side to side. Called tread wear indicators, they become flush with the tread when it wears to that 2/32nds point.
In my opinion, tires become less effective before that point.
Do you have questions about your car? We can help. E-mail globedrive@globeandmail.com
