LED Lamp Reliability: Design and Production Process Impact 1999-01-0389
Within the automotive market the application of LEDs for rear lamp functions or CHMSL has been highly increased.
The styling aspect as well as short rise time as a safety feature are the main reasons for this effect. In designing an LED application for both, CHMSL and rear lamps one has to take into account reliability of the total system.
LEDs, as single components, have reliability higher than any incandescent or halogen bulb: from this point of view the LED rear lamp reliability should be higher than traditional rear lamp reliability.
On the other hand, at the moment ECE specifications allow using LEDs as light source for rear lamps just in the case that the rear lamp is sealed. As a consequence if some LED fails it will be necessary to substitute the complete rear lamp: this will be a potentially very high maintenance cost for the final customer. Therefore LED rear lamp reliability has to be considered specifically under these boundary conditions.