Are HID lights too dangerous?

[Simon Linton]

I was discussing HID light conversions with Phil Wright yesterday and he mentioned some points that I hadn't found in any of the websites selling the units.

I thought I'd share these with anyone who is considering (as I was) a HID installation in their car.

The "warm-up" period of the HID gas discharge bulb makes them suitable for dipped beam use ONLY - you can't just flick them on as you would a normal bulb.

Current legislation says that HID installations must be combined with automatic washing and levelling systems; this is to stop beam scatter from dirty lenses and the danger of blinding oncoming drivers with a heavily loaded car.

So far, so good - but the real and literal killer comes with the actual bulbs themselves.

What I didn't realise is that the HID system requires the bulb to be POSITIVELY pressurised, up to some 7 atmospheres in larger discharge bulbs.

So unlike the normal evacuated bulb, the HID is a glass-coated hand grenade waiting to explode.

This is why bulb replacement is a dealer fit item on many standard HID-equipped cars, a dropped bulb when you're replacing it will leave your face looking like Freddy Kruger's and you may very well be blinded into the bargain.

The other danger is a low-speed headlamp busting accident; what would normally be a simple glass replacement could turn into a small bomb going off and injuring passers-by, especially since aftermarket installation means that the headlamp unit is not designed for a positive pressure bulb inside it.

I certainly won't be fitting HID into my car and I would recommend that other readers don't either.

If you get a full HID-designed unit that's another matter, but the standard headlamp is not a HID-compatible item.

Simon Linton, 850/70
Register Keeper

Doing a lot of motoray mile I tend to find that cars fitted with these bulbs tend to blind oncoming traffic regardless if they are on main beam or full beam.

However I had a new S40 as a loan car whilst my car had some work done to it and I have to say that Gas Discharge bulbs do give a better field of vision when driving at night.

[sholtby]

I'm not a fan of these lights either. I find them dazzling and they seem to cause a flickering blue light which can be confused with emergency vehicles.

Simon

Just a few comments on your post.

The HID stystem can be used on main beam - I had after market kits fitted to both high and low beams on a V70R AWD. The ignition is almost instant (well it was on mine anyway).

Since the bulbs are designed to last the lifetime of the car then bulb replacement is not usually performed by the motorist.

In a low-speed headlamp busting accident - isn't the lens already busted so would not the same problem occur on a standard HID system.

Reputable companies like Philips would have considered these issues - the problem occurs when you purchase cheap Asian items that have a lower quality.

Karl

Simon,

Don't let the motorists friend Richard Brunstrom (Chief Constable of North Wales) hear about your findings, he will probably want to outlaw these as well as tinted windows (see tinted widows post) and nanny us to death with this as well!

Chris

[john d]

Simon,

I was discussing this type of lighting with a friend last Friday. He has these lamps fitted to his BMW, and one failed a while ago. He expected to be able to replace it with a "£4.95 lamp from Halfords".

When he took it to the dealer, they said the good news would be £70 for a new lamp, while the bad news would be £300+ if the control box needed replacement! Unfortunately, his was bad news, and to say he wasn't best pleased would be putting it mildly.

Whilst I'm sure these lights represent progress, I can't reconcile it at this level of cost, and I've taken this "improvement" off my list of things to do.

John