Quote:
Originally Posted by brian1950
It is a well known fact that LEDs will not tolerate flickering. I have had several sets burn out or go brown in the centre and weaken in brightness after only a few months, so I do know what I am talking about.
I would respectfully suggest you do more research regarding LED bulbs. They do not tolerate cold monitoring, or as you refer to it as lamp check signal.
|
As an electronic engineer with over 30 years design experience I have used many different types of LED’s in various applications and this is one of the most absurd things I have ever heard of.
There are many reasons why LED’s die but I can assure you pulsing them within their specs is not one of them.
If I get time later today I’m going to have a look at this lamp check signal on my own vehicle with a CRO to see if there’s anything unusual with it.
If it’s a simple 0-12V switched signal, then there is no possible way this would cause premature failures.
If the signal switches from positive to negative there is a possibility this may cause issues if the lamp unit is not designed correctly as it would be momentarily applying reverse polarity voltage to the LED’s which they don’t like. If this is the case, the cause is a design issue with the lamp unit and not the fact that the LED’s are being pulsed.
As an example of pulsed LED’s in an automotive environment; have a look at the brake/tail lights of any high end Audi or VW with LED lights. You will notice there is a bunch of LED’s that are used for both the tail and brake lights. These are pulsed very quickly to reduce their brightness when the tail lights are on without the brake lights, the pulsing stops when the brake lights are on to provide the added brightness for the brake lights. You will probably also find this setup on other Euro cars and from memory the later version of the Prius is setup like this too.