One day, switched on the orange bulb warning light.

Well okay, I need to find what bulb does not light, (told to myself). After a day the warning light switched off automatically.

I don't understand perfectly it, I checked all bulbs, all works as I expected.

My conclusion is the bulb checker system is a tiny bit unstable maybe.

 

Do you have somebody same experience?

 

(About a month ago, I realized the same thing, but on that case, one of bulb was a little bit sooty in inside, but it works.

Maybe emitted some metal parts of filament as steam to inside the bulb.
I replaced the affected bulb to a new one, the warning light turned off.

My conclusion was at that time, the bulb checker system is very sensitive)

Edited 26 July, 201312 yr by ujtordai

This isn't uncommon in cars.  The bulb has blown but not catastrophically - the broken ends of the filament are just hanging in the bulb.  If the ends happen to come into contact again whilst the car has the bulbs energised then the broken ends weld back together again and hey presto, a functioning light bulb.  Had this for about a year in a Mini of mine - every so often the sidelight bulb would break but then after a little while it would reconnect again.  Tends to be more common in sidelight type bulbs, as when a headlight bulb blows it tends to do so fairly catastrophically and doesn't leave floating ends of filament around!

 

Michael