Before we start, we’d like to make one thing very clear. AHO has nothing to do with BS4.
Bharat Stage is an emission norm which is a regulation in India for automobile manufacturers. AHO is a passive safety norm which is not a regulation, but an implementation norm.
In other words, vehicles sold in India are required to be tuned or regulated within the limits prescribed in BS4, while AHO is a feature that is required to be implemented in the vehicles. Both of them were enforced last year (2016) for brand new models. From tomorrow (April 1, 2017) all existing models of vehicles must have satisfied both the norms. BS4 and AHO are simultaneous implementations, they are not codependent.
Let us elaborate on AHO first.
AHO, known as DRL, was introduced as a norm in Europe several years ago because many European countries have low visibility effected by the climate. The regions are cloudy most of the time, and rain and snow make things even worse for pedestrians and passersby. This caused numerous accidents on road.
As a solution, some automakers voluntarily wired the low beam of headlamp to the ignition, so that the low beam is ON whenever the engine is running. Then, the European Union mandated that DRL (Daytime Running Light) be installed on all vehicles, and set standards/regulations with regard to the intensity and spread of the light, for various types of automobiles.
The case was similar in the UK, Russia, Canada and the USA, but there were several disputes pertaining to the minimum and maximum light intensity of the DRLs, the added cost to the vehicle, and ironically, the potential safety hazards by the use of DRL. In Australia DRLs are allowed but not mandated.
All this started in the 1970s!
Close to 40 years later, DRLs were introduced in Indian vehicles as a fancy feature. After more than a decade then, the government decided to implement the AHO with some regulations.
AHO does not literally mean Always ON Headlamp. This is just an easy way out the local manufacturers are taking. DRLs can very well be AHO, provided they are tweaked to perform within the limits set for AHO.
Some of the new vehicles launched in 2016 have LED DRLs that are tuned to perform as AHO, instead of having the low beam ON all the time. But many new vehicles, and the ones that are to be introduced next month, have always ON low beam which is not a great news.
Advantages of Low-Beam AHO
Works out to be an inexpensive workaround for the manufacturers. The price of the vehicles remain almost the same.
Downsides of Low-Beam AHO:
1 – Power consumption within the vehicle becomes higher. This gives a comparatively higher load to the magneto/alternator, which is transferred to the crankshaft. Consequentially there will be a drop in mileage in the vehicles with this type of AHO, by as much as 1 kmpl. This is in case of halogen bulb for low beam. After a year or two, when every vehicle (especially two-wheeler) on road has around 1 kmpl drop due to wear & tear, the collective consequence of burning more fuel could really high.
2 – In India the duration of vehicle idling is significant due to excessive traffic. If the reflector dome within the headlamp is not redesigned, the prolonged high heat from the bulb will cause the reflector to fade and deteriorate much earlier, especially during vehicle idle condition. This consequence will be more negligible when LED DRL is tuned to be AHO.
3 – AHO would be more useful on highways than in city. In cities with dense traffic, AHO seems less needed.
4 – If the vehicle doesn’t have the throw/angle of low-beam adjusted properly, it will cause irritation to the pedestrians and on-coming drivers. This has the potential to cause accidents. In case of an LED DRL, such an incident is less likely to happen.
5 – There is another potential disaster that could be accelerated by AHO in India – Global Warming. After a year or two, when most of the vehicles in the city would have the halogen lamps always lit, think of the collective heat that will be emitted. At a traffic signal, where heat radiation is already felt high, those hundreds of vehicles would contribute to much higher heat because of always ON halogen lamp. This will accelerate the rise in temperature of the region.
6 – In European countries, as said before, DRL was implemented as the weather is foggy most of the time. India is a very diverse country. Foggy roads are witnessed mostly in North India and rarely in South India. This is why Solar Farms are setup mostly in the central and southern part of the country, given the closer vicinity to the equator and brighter days. So, AHO will have good purpose in the North, but not at all in the South.
7 – When the battery of the vehicle is down, or when the fuel is very low, the user may not be able to crank the vehicle as many times as he would be able to in a vehicle that doesn’t have Always ON Headlamp with halogen bulb. For instance, if you could crank the engine 10 times before, with AHO, you would be able to crank the engine only 7-8 times now. This is just a vague example.
Dear readers, please let us know what you think about these points, in the comments section below. We are not debating the implementation of AHO, we are just suggesting that the LED DRLs be turned into AHO rather than having the low beam ON all the time. What do you think?