ML 55 AMG 2001
Replaced ordinary bulbs in the front parking lights (or are they marker lights? I mean the weakest bulbs within the headlights assemblies) with LEDs.
(Please do not advise that I shall change them back. I know that this can solve the problem, thanks)
2 weeks later I noticed that these LEDs are burning allright when the engine is off, but are flickering randomly (I would even say wildly) when the engine is on. Why?! Voltage seems to be OK - last time I measured it was 12,8 V with engine off vs. 13,6 with engine on.
Please provide the year of your vehicle.
I think your lamps are simply poorly designed/manufactured/defective.
"Please provide the year of your vehicle."
Hate quoting my own self.
"ML 55 AMG 2001"
2001 is the year
"I think your lamps are simply poorly designed/manufactured/defective."
Very probable. But why do they work flawlessly when powered by the battery (only)?!
Sorry! The year was in my blind spot 😳
I don't why they only work on battery. I would have to examine them.
It's possible that they have poor ripple rejection (introduced by alternator). It could be a faulty power supply triggered by charge voltage. Many possibilities.
"Many possibilities."
Thank you, Sir. This is approximately what I feared to hear. Sounds like time to get hold of someone who knows the word "oscilloscope", and these beasts are rare in our forests 🙂
Would posting a photo increase chances of a positive outcome?
personally I wouldn't waste my time. Defective. Return for refund. Try better product.
"Defective. Return for refund."
I sort of forfeited the return time limit - lazy me. But those are peanuts anyhow.
"Try better product."
Right you are - that is what I will most probably end up doing. Wish I knew a better product - I thought I bought the best one of all I could get hold of - by far not the cheapest price, good customer feedback... 🙁 Will have to search further. My severe limitation is the diameter - since they have to be inserted from the rear into a very tight opening, the LEDs have to be very slim 🙁
this is why I am avoiding LED
"this is why I am avoiding LED"
I understand you very well. Your point is very well grounded.
As to me - it is not that I like problems - I just love shiny things 🙂 People have weaknesses, and I have mine - I love the way my LEDs shine. They are so much better than ordinary bulbs, when - and as long as - they actually shine... 🙂
Should be at least 14.5 volts at idle. How old is the battery?
the lights should work perfectly fine with anywhere between 12.0 and 15.0V
Modern vehicles use a whole range of different charging voltages.
"How old is the battery?"
6 y.o.
BUT the lights are OK when running from the battery. They start flickering when the engine = alternator engage.
"Should be at least 14.5 volts at idle"
My charging voltage is temperature-dependent, but not even in coldest winters higher that 14,2 V. Reason: this is the way the voltage regulator is set up by manufacturer 🙁
"the lights should work perfectly fine with anywhere between 12.0 and 15.0V"
That is what I expected. Uuups. Took a new (spare) LED of the same type (yes, I have plenty of spares). It works flawlessly, when fed with 13,6 (or even 14) V from my adjustable power source used for testing purposes.
I hate miracles.