
L.E.D. Resistor Help
I have 2017 R1200R
Recently installed a Puig fender eliminator kit that also has a L.E.D. license plate light replacement.
Everything works and looks great. However, the new L.E.D. light is tripping my dash warning light for bulb malfunction.
Since the L.E.D. is not canbus I believe I need a resistor to match the previous bulbs load, voltage, etc.
Does anyone have any experience and/or fixed this issue? I do not know how to determine wich resistor I need to install. Puig has been no help.
Thanks in advance!

Welcome to the forum! There are a couple of threads in the Similar Threads pane at the bottom of the screen that seem to touch on the issue. Good reading while you wait for more current answers.

It's All Math
Hi,
Using Ohm's law where current (amps) = voltage divided by resistance, you only need two of the values to figure out the 3rd. Once you have all three values multiply current (amps) times volts to get watts. Again if you know two of the values you can calculate the third. Calculate your original load, using the formula's figure out how much resistance is needed to equal the original load than calculate the wattage of the resistor needed.
Later,
Norm

Welcome to the forum!
I did some looking around and any cures past purchasing a whole aftermarket specific LP light ended up either not working or only working a short time.
I guess to [I]really[/I] attempt to get this to work, you would have to get a few LED’s and some lab grade resistors and make up a perfect match.
OM

[QUOTE=gloucesterman;1152900]Hi,
Using Ohm's law where current (amps) = voltage divided by resistance, you only need two of the values to figure out the 3rd. Once you have all three values multiply current (amps) times volts to get watts. Again if you know two of the values you can calculate the third. Calculate your original load, using the formula's figure out how much resistance is needed to equal the original load than calculate the wattage of the resistor needed.
Later,
Norm[/QUOTE]
Thank you for your the info!
The original bulb and wire, I'm unable to locate and test for the above values.
Far as I can tell from the bulb itself from online, is 5watts12 Volts.
Is this enough to go on?

Yes
Hi,
Yes, 5 watts at 12 volts using Watt's law and basic algebra will give you .42 amps draw per bulb which you can now plug into Ohm's law to get the resistance of each bulb, 5.04 ohms.
Later,
Norm
PS
Watt’s law  5 watts = amps X 12
Algebra – amps = 5 / 12 or .42 amps per bulb
Ohm’s law .42 amp = 12/resistance
Algebra – resistance = 12 x .42 or 5.04 ohms per bulb

Correction: R=V/I so 28.8 Ohms for the resistor. Or, P=V2/R so R=V2/P 144/5=28.8 ohms

From the Department of Keeping it Simple
[url]https://www.electricalsafetyfirst.org.uk/wattstoampscalculator/[/url]
OM

Close however keep in mind the resistor must be placed in Parallel. so this changes some values.
Gator

[QUOTE=Omega Man;1153150]From the Department of Keeping it Simple
[url]https://www.electricalsafetyfirst.org.uk/wattstoampscalculator/[/url]
OM[/QUOTE]
What, we can't do simple math anymore?! ;)
Now if you want to get picky, there may be a more complex impedance at play here so you would need to look at inductance and capacitance too. Then there is the fact that the voltage varies from about 12.6 to 14 as load changes on the bikes electrical system, and then of course, the phase of the moon has to be considered...

[QUOTE=sharsman;1152860]I have 2017 R1200R
Recently installed a Puig fender eliminator kit that also has a L.E.D. license plate light replacement.
Everything works and looks great. However, the new L.E.D. light is tripping my dash warning light for bulb malfunction.
Since the L.E.D. is not canbus I believe I need a resistor to match the previous bulbs load, voltage, etc.
Does anyone have any experience and/or fixed this issue? I do not know how to determine wich resistor I need to install. Puig has been no help.
Thanks in advance![/QUOTE]
If Puig can't supply a light that works and is compatible with your bike I would send their junk back to them. We shouldn't need to buy stuff and then find workarounds for their crap not working.

????
Hi,
azgman your confusing me, ohm law is I = V/R, that’s a formula, so when you move a value from one side of the equal sign to the other the function that took place on the original side is reversed, ie was multiplication, now division, was addition now subtraction???? The same with Watt's law W = I x V. So when I plug in his values to Omega Man’s link it comes up .42 amps draw per bulb. And resistance per bulb is 5.04 ohms. His resistor will be based on the difference between the stock bulb and the new LED's. Also Gator using these formula's the fact that it is being wired in parallel which is needed will not change the values??? The bike is spec'ed at 12 volts so that is what all of the electrical spec's are based on. Inductance and capacitance, yeah let's keep it simple!!!
Later,
Norm

[QUOTE=gloucesterman;1153199]Hi,
azgman your confusing me, ohm law is I = V/R, that’s a formula, so when you move a value from one side of the equal sign to the other the function that took place on the original side is reversed, ie was multiplication, now division, was addition now subtraction???? The same with Watt's law W = I x V. So when I plug in his values to Omega Man’s link it comes up .42 amps draw per bulb. And resistance per bulb is 5.04 ohms. His resistor will be based on the difference between the stock bulb and the new LED's. Also Gator using these formula's the fact that it is being wired in parallel which is needed will not change the values??? The bike is spec'ed at 12 volts so that is what all of the electrical spec's are based on. Inductance and capacitance, yeah let's keep it simple!!!
Later,
Norm[/QUOTE]
I = V/R, to find R, multiply both side by R this gives I * R = V * R / R. R/R = 1 so I * R = V. Next divide both sides by I, so I/I = 1 and gives R = V/I. To prove this, take the equation I = V/R If V=12 and R=5.04 Ohms then I = 12/5.04 = 2.38 Amps, not .42 Amps. 12/28.8 = .416 Amps

[QUOTE=PGlaves;1153193]If Puig can't supply a light that works and is compatible with your bike I would send their junk back to them. We shouldn't need to buy stuff and then find workarounds for their crap not working.[/QUOTE]
^^^this^^^
Unless, of course, the description (not the fine print) indicated something else was needed...AND they told you what it was. I'm becoming a "find a good dealer and build a good relationship with them" kinda guy; to the point where they might even advise me on aftermarket ideas that they may not sell (in exchange for your ((my)) willingness to pay the briksandmortar premium.
ok back to the thread...

1 Attachment(s)
The warning light is tripped by the current draw in that branch not being within the computer's "spec window"; it can be either too high or too low to cause the warning light to come on.
So the first step is to determine if the replacement light is drawing more or less current than the stock setup.
If it draws less current, then a resistor in parallel would fix that; you need to know what the [U]difference[/U] in current is  the stock vs. the Puig  to figure the resistor's value.
If the Puig lighting draws more current, put a piece of black tape over the warning bulb.
[ATTACH=CONFIG]72266[/ATTACH]

[QUOTE=gloucesterman;1153199]Hi,
Also Gator using these formula's the fact that it is being wired in parallel which is needed will not change the values???
Norm[/QUOTE]
The value of the LED and the resistor in parallel will be different. When you have two devices in parallel the combined resistance is measured at the point where the two devices connect. Since you will now have two paths of current flow the resistance will be lower. Also, this means that it will always be lower than either device by itself.

[QUOTE=Pauls1150;1153207]T
If it draws less current, then a resistor in parallel would fix that; you need to know what the [U]difference[/U] in current is  the stock vs. the Puig  to figure the resistor's value.
If the Puig lighting draws more current, put a piece of black tape over the warning bulb.
[ATTACH=CONFIG]72266[/ATTACH][/QUOTE]
Send it back!

Hi,
You're right. My bad. That is a per bulb value. His resistor for each bulb will be the difference between his original load and the new led load. Once he has that difference he can figure out what wattage he needs for each resistor. I would up the wattage rating on the resistor to take into consideration overall voltage fluctuation.
[url]https://www.rapidtables.com/calc/electric/wattvoltampcalculator.html[/url]
5 Watts
12 Volts
.42 Amps
29 Ohms
Later,
Norm

So a couple of people caught what I was saying about parallel resistance. There is also the whole what does the canbus actually look for?
Lastly I have to say as usual I completely agree with Paul if the vendor sells a product that requires you to design and engineer a work around send it back. What I do know about canbus is depending on where you tie in you can effect any and everything on that part of the bus. IE if you tie in at the wrong spot you can cause all kinds of gremlins!
Gator

It Is Simple
Yes Gator,
But we are not talking about a parallel circuit here, and yes it is different but this is a simple series circuit. All he is trying to do is mimic the load that the computer originally saw on that circuit. I can't even imagine what might happen if you wired a resistor in parallel on a BMW!
Later,
Norm

Well, it seems a lot of anger directed at Puig. While I don't know anything about Puig or their products....I thought I would take a look.
I can't find Puig supplying lights [url]https://puig.tv/en/tuningmotos/licensesupports/licencesupport?bike=12860[/url]
It seems RevZilla has a kit with a light [url]https://www.revzilla.com/motorcycle/puigfendereliminatorkitbmwr1200rr1250rrs20152019[/url]
There is a caution that [QUOTE][I]This product FITS your 2017 BMW R1200R
Fitment Notes & Exceptions
Not compatible with OEM turn signals
Requires splicing of OEM license plate light harness[/I][/QUOTE]
It would be nice if the OP could return and give us an idea how the kit was supplied.
OM

[QUOTE=Omega Man;1153260]Well, it seems a lot of anger directed at Puig. While I don't know anything about Puig or their products....I thought I would take a look.
I can't find Puig supplying lights [url]https://puig.tv/en/tuningmotos/licensesupports/licencesupport?bike=12860[/url]
It seems RevZilla has a kit with a light [url]https://www.revzilla.com/motorcycle/puigfendereliminatorkitbmwr1200rr1250rrs20152019[/url]
There is a caution that
It would be nice if the OP could return and give us an idea how the kit was supplied.
OM[/QUOTE]
I did finally get a response from Puig. They stated I received an older version kit. Even though it was made specifically for my motorcycle, they later removed the l.e.d. light and expanded the hole on the mount to accept the o.e.m. bulb. The kit I received, I was unable to pass through the bulb and bulb holder to mount. They are sending me an updated part. However, I have misplaced the original bulb, bulb holder, and wire. So, it's not going to do me much good.
I really appreciate everyone's help.


[QUOTE=gloucesterman;1153254]Yes Gator,
But we are not talking about a parallel circuit here, and yes it is different but this is a simple series circuit. All he is trying to do is mimic the load that the computer originally saw on that circuit. I can't even imagine what might happen if you wired a resistor in parallel on a BMW!
Later,
Norm[/QUOTE]
Are you positive the canbus is only looking at load? I am not. I am trying hard to understand canbus as I recently purchased a 2016 RS. Most of my Experience is with Airheads and older Electronics and no I am not an Electronics guru. Very limited knowledge in fact. I can tell you a series resistor will not work correctly.
Gator

Buy one of [COLOR="#0000FF"][B][URL="https://www.superbrightleds.com/moreinfo/flashersloadresistors/ledmarkerlamploadresistorkitsidemarkerledlighthyperflashingwarningfix/191/832/"]these[/URL][/B][/COLOR] and connect it in parallel with the bulb (not in series).