Long lamp lifetimes

I have a 1991 Q45. The middle brake lamp went first, and that was perhaps in 2001. I've had two other brake lights go since then. The rest of the lamps are original, except for a real tiny one on the dashboard that lights up the recirc button. I think I have one other dashboard light that I need to get to. Those tiny bulbs are about $13 each and I have to take the radio out and the dashboard apart to get to them.

My minivan was two years old when the center brake light went, and it's the same bulb number as the Infiniti. I know that there are regular and long life versions of the bulb. I went with the long life because that's all the store had in stock. It came in a pack of two, which is a good thing because it will probably burn out again in 2011.

Sounds like poor design to me. All lamps blow sooner or later. So the least they can do is make them easy to change.

What does make lamps last longer is restricting the peak voltage they get. Have you ever measured the Lexus? Trouble with this is it also makes a big difference to the light output of incandescent lamps.

The cornering lamps were tough to get at because you had to pop out the light assembly to do it and the service manual was not sufficiently detailed in instructing how to do it. One of those things that you need to actually see done to be able to yourself easilly. I am now an expert with the expertise aquired the hard way.

What makes lamps last longer is lamp design. The voltage that car lamps get is (surprise) 12 v in all modern cars. Build a better lamp (excellent seal and long-life filament) and it lasts longer.

I notice that all the cheap makers (ford etc.) get through bulbs all the time, my Lexus doesn't, neither do other Lexus I work on. I assume that the initial bulb quality is higher and that voltage spikes are more controlled, also things like dash bulbs are electronically fed, rather than just a rheostat. Bear in mind that the indicator bulbs that the OP had blow may have been put in specially for his country by the importer, so may not have been "genuine" bulbs. My Lexus has a rear interior bulb gone (9 years old) An LS I know has had an interior bulb and one brake light bulb go (10 years old)

mrcheerful

Surprise - it's not. They run at the alternator output voltage when the engine's running. And this is approximately 14 volts. Which can be as high as 14.5 or so without there being a fault. But some alternators have a slightly lower peak voltage than others - and this can have a great effect on lamp life. As could voltage drop in the wiring.

Other things that effect lamp life are the temperature it runs at - a small housing might make a difference - or vibration.

I doubt Lexus make their own lamps.

I have a 1997 Dodge Dakota, original owner and only lamp I have replaced is the

compare that with ordinary ford fiestas and the like in uk, they usually have several bulbs in the rear lamps/brake lamps before they are two years old.

mrcheerful

My 1991 Q45 just had a headlamp burn out. It's the first time. So that's 14 years for the headlamp (low beam,) about a decade for the tail lamps, and the signal lamps and side marker lamps are still going. I never had an interior lamp go except for the real expensive and hard to change one in the dash. But even that one probably lasted a decade.