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Discussion Starter · #1 · (Edited)
I replaced my rear blinker W16W bulbs with LED's because I like the instant on-off look. I was sceptical at first about the light output. But they look great and are at least as bright as the old bulbs!

I expected hyperflash or burnout-warning, but this one I don't understand:

There is no hyperflash; the flash-rate is exactly the same as with the old bulbs. There is no Burnout-warning for the left blinker, but it IS triggered for the right blinker...which is exactly the same "bulb".

I'm clueless, what could cause this inconsistent behaviour? :confused:
 

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Hmmm... I suspect it's a function of the 'digital' electronics triggering the hazard function...

In 'olden days' (last year!) indicators would have analogue electronic circuits, with a bi-stable circuit, (discharging through a capacitor/resistor/transistor/diode combo) and then this operating a relay for the higher voltage, that made the familiar 'tick-tock' of indicators, which now has to be fabricated! I belive that they may now be digital systems, hence the fact that they still flash at the same rate despite the resitance and thus current draw being completely different.

However, I can only assume there's some 'sensing' done and this is causing the hazard function to be activated instead?

Just a guess, but there's no way in an analogue system the behavior you describe would happen.
 

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It is strange, you'd expect both to be triggered. It could be that the bulbs have very slight differences, and the current drawn could be different for each bulb.

You should try switching the bulbs around, and see if the left blinker gets the warning. If that's the case, then I can only assume that one bulb is drawing less current than the other. ( a lesser current will activate the warning).
 

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You should try switching the bulbs around, and see if the left blinker gets the warning. If that's the case, then I can only assume that one bulb is drawing less current than the other. ( a lesser current will activate the warning).
I was thinking the same thing!
 

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Discussion Starter · #5 ·
You should try switching the bulbs around, and see if the left blinker gets the warning. If that's the case, then I can only assume that one bulb is drawing less current than the other. ( a lesser current will activate the warning).
I switched the bulbs and still only the right one triggers the warning. :(
I forgot to test without any bulbs, but it seems its the detection thats different or defective, not the bulbs. :confused:
 

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Have you checked your blinker fluid level?
 

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I switched the bulbs and still only the right one triggers the warning. :(
I forgot to test without any bulbs, but it seems its the detection thats different or defective, not the bulbs. :confused:
Put both original bulbs back and check that the warnings have reset without further interaction required anywhere.

Then, remove only the left one. See if the warning appears. If not, then obviously that side has no warning capability (which would be surprising). If the warning appears, then the issue is due to borderline differences within the internal impedence of the real bulb versus your replacement bulb which can be solved as described below.

Either way, whether bulb-blown warnings exist or not, you need to place an parallel resister to remove some impedence from the new bulb assembly. Some LED replacement bulbs have built-in resistors to prevent this problem so that its characteristics are so similar to filament bulbs that such warning systems do not get triggered.

Do the original bulbs have a Wattage (25W?) and Voltage (12v?) level markings on them?

What are the Wattage and Voltage level markings on the replacement bulbs?

With this information, the parallel impedence can be calculated and you need to put such a resister in parallel with the bulb. This will take some current around the bulb.

To explain it using a water analogy, imagine you have a water stream passing through your village. You then have a watermill where the water wheel spins with the flow of water resulting in some benefit such as milling the corn or whatever. The water flow is your current, the water wheel is your bulb, and the cornmilling is the light produced by the bulb.

Now you replace the water wheel with a different spec of water wheel that spins with greater resistance in its mechanics. The water flow will still make the wheel turn, but at a lower speed. As a result, the water flow is slowed down and starts to backup further upstream.

The bulb blown warning is detecting the slow-down in water flow and trying to warn against the risk of flood upstream.

The solution is to make a channel just before the water wheel to take some of the water around the water wheel and rejoin the stream after the water wheel. As a result, the flow of water continues and the warnings of water flow (bulb blown) disappear. If the channel is too small, it will not divert enough of the water and will be inadequate. If the channel is too large, it will divert too much water and starve the water wheel.

The size of the channel is the resister that needs to be placed in parallel around the bulb to draw some of the current flow and thereby cause the total current flow to be enough to not trigger the alarm.
 

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Discussion Starter · #10 · (Edited)
Its not the detection system; just tried without any bulb and then the warning is triggered on the left side as well. :( Still strange the LED bulbs only cause this behaviour on the left side...

The original bulbs are 16W 12V. The LED's are 5W. I do have some 50W 3Ω load resistors lying around with splice taps. However being a non-ideal solution, that would be the last resort. ...But I guess its the only option left.
 

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Yes, it seems the bulbs are borderline in their ability to "simulate filament bulbs", it needs a small tweak. Would agree that the load resisters should be a last resort, ideally a bulb with the correct impendance (simulated or natural) will serve best.
 

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OK my friend I think maybe I can help you
I ve had the same problem with my old car where I replaced
the rear bulbs with LED lights. After a while strange things began to
happen to my car such as: error readings, right flash indicator activated
instead to left(!!). Once all the lights went on in the same time!
So this is what was the problem..
My new LED lights operated in different voltage than the bulbs thus
confusing the car's computer and forcing it to redistribute the voltage
with that "x-files" manner.
I'm not a technician to tell you exactly what my technician did, but
as he told me he just adjusted the computer to be able to "adopt" the
new voltage
I think a visit to a technician will resolve your problem.
I hope I helped and.. sorry if I troubled you with my bad english :eek:
 

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Discussion Starter · #13 ·
Ok, thanks Larry. I'll ask a mechanic if this adjustment is possible.

For the mean time I installed a resistor for the right side, which solved the issue. The left side works great without any mods.
 
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