turn signal frequency increase

[mrfochon]

As I was driving today and approached a stop I turned on my turn signal on, after 10-15 sec the frequency increased.
Was surprised as I never had this behavior before. So thought it s a simple mistake.
Next light it happened again.
Then never again. So thought to share here just for fun

And idea ?

[Qsilver7]

You may have a bulb that is starting to burn out/die. When a bulb’s filament burns out/fails…the resistance in the circuit changes which can cause the blinking/flashing frequency to increase (get faster).

[mrfochon]

Originally Posted by Qsilver7

You may have a bulb that is starting to burn out/die. When a bulb’s filament burns out/fails…the resistance in the circuit changes which can cause the blinking/flashing frequency to increase (get faster).

Thank you. Read that elsewhere online for older cards. Will keep an eye on that.

Funny enough I get the left turn light malfunctions error sometime but then when I check I don’t see anything out of function.

Cheers

[Qsilver7]

With all the LEDs on these newer BMWs…I don’t know if BMW still uses a design that will replace burnt out bulbs. In the e38/e39/e53 era…there was a replacment feature…in some of the important lighting positions like turn indicators.

Since in the US market, many of these bulbs had 2 filaments…one high watt & one low watt filament. If one of those filaments burnt out…the LCM would adjust the illumination of the remaining filament so that you still had turn indicators or parking lights. The parking light illumination uses the low watt filament...and the turn indicator uses the higher watt filament.

So many owners would simply look at the exterior and see the bulb flashing and assume the bulb was okay. But if they physically went into the light assembly and could see the bulb…it was clear that the one filament was burnt out.

Again, I don’t know if BMW still uses this design principle or even use incandescent bulbs with two filaments. But you may need to check deeper if you’re getting a check control warning about the left side. It could be front, side, or rear light assembly.

Do you have LED headlights or Xenon? I don’t think the LED headlights have any incandescent bulbs at all…but the Xenon’s do use an amber incandescent bulb PY24W.

[mrfochon]

Yes headlight bi-xenon with turn signal that seems bulb but not sure

[Qsilver7]

Originally Posted by mrfochon

Yes headlight bi-xenon with turn signal that seems bulb but not sure

I would check the bulb on the side that is blinking fast to see if one of the filaments is burnt out...or has broken loose on one side and is intermittently losing contact as you drive around...which is why sometimes the blinking could be normal and other times not normal.

Here's the info about the replacement lighting feature of the LCM (light control module) during the e38/e39/e53 days...again, BMW may have incorporated this design detail into the newer gen BMWs but the module that controls the lights could be the FRM, FEM, or BDC module.