BMW R1200R R1150R/T F800 K1200R R1100R/T R1250R RnineT Message Board

I'm a fan of replacing the side / parking / position light bulb with an LED equivalent because I think it stands out even against the headlight beam to make you very noticeable to other road users.

With Canbus, of course, the resistance of an LED is too high and is interpreted as a bulb failure so the supplier has free-issued a resistor to fit in parallel with the circuit.

Has anybody here got any experience of the best place to fit the resistor? the obvious place is at the in-line connector inside the headlamp unit but there's a warning that the 47 Ohm 5W resistor can get hot during operation and so to avoid plastic!

I'll also be fitting 2 x Xenon +50% white H11 bulbs so perhaps the above exercise is a bit superfluous.

Hi Shakey...I think a resistor put inline on a LED light would let the light fool the canbus; but I have no other information to give. I remember seeing somewhere a set of LED or maybe HID lights that came with a resistor...where I can't remember.
I think all the turn lights would each have the same resistance... what about the brake light? The resistance a given light has might be listed in the spec.s.???
I would be interested in finding the resistor values for all the lights on our bikes.

Robert

[quote="Shakey"]I'm a fan of replacing the side / parking / position light bulb with an LED equivalent because I think it stands out even against the headlight beam to make you very noticeable to other road users.

With Canbus, of course, the resistance of an LED is too high and is interpreted as a bulb failure so the supplier has free-issued a resistor to fit in parallel with the circuit.

Has anybody here got any experience of the best place to fit the resistor? the obvious place is at the in-line connector inside the headlamp unit but there's a warning that the 47 Ohm 5W resistor can get hot during operation and so to avoid plastic!

I'll also be fitting 2 x Xenon +50% white H11 bulbs so perhaps the above exercise is a bit superfluous. [/

Sounds like you bought your gear already, but just to add, the BMW factory LED indicators plugged right in to my '12 r1200r (same harness connectors and all) and worked w/o any lamp error at all. In fact it was all of 30 min to install all 4. Very much brighter and more noticeable then the stock incandescent. The factory LED tail did require dealer coding, as it only used a single positive (as opposed to the bulb version, which has two filaments) - so brake/tail brightness was done by varying voltage, hence the recoding. It worked from the start, as the lamp controller has a safety feature in case a filament is burnt, but it throws a lamp warning until it's coded out.

I also installed a "oneoffmotorsport" hid kit (low only- wanted to retain flashing on high- hids take time to warm up- so not effective for flashing highs) that kit went in w/o issue and no error as well. 2500 or so miles (had a mild winter here) later and no prob. No flashing at me either, as I made very sure aim was spot-on. HID is very bright and very noticeable, I would do it again in a heartbeat.

So there you go...

Found the information I was looking for... ohm's law.... measuring the resistance with the old bulb against the new bulb should give the difference. Radio Shack here I come...

http://www.ohmslawcalculator.com/ohms_l ... ulator.php

Robert

mchad wrote:... the BMW factory LED indicators plugged right in to my '12 r1200r (same harness connectors and all) and worked w/o any lamp error at all.

I would expect the BMW factory assembly to have the required resistors built-in but I'll try a straight swap to see if it works.
I'm not too impressed by being sent a couple of resistors when they do make a plug in line unit for just 2.50 GBP but hey, the bulbs are cheap enough so I've ordered a couple of those as well.

I'll report back when I have finished the installation.

redwing wrote:Found the information I was looking for... ohm's law.... measuring the resistance with the old bulb against the new bulb should give the difference. Radio Shack here I come...

http://www.ohmslawcalculator.com/ohms_l ... ulator.php

Robert

Yeah V=IR so R = V/I or I = V/R

What we really need to know is whether the canbus system detects loop integrity by measuring the current flowing in the circuit or by measuring the resistance / impedance.
It's my experience that other systems that monitor loop health do so by mens of resistance monitoring so a very high impedance LED will effectively emulate an open circuit.

Of course, I could be wrong

I'll be quiet now...

Robert

Shakey wrote:

redwing wrote:Found the information I was looking for... ohm's law.... measuring the resistance with the old bulb against the new bulb should give the difference. Radio Shack here I come...

http://www.ohmslawcalculator.com/ohms_l ... ulator.php

Robert

Yeah V=IR so R = I/V or I = V/R

What we really need to know is whether the canbus system detects loop integrity by measuring the current flowing in the circuit or by measuring the resistance / impedance.
It's my experience that other systems that monitor loop health do so by mens of resistance monitoring so a very high impedance LED will effectively emulate an open circuit.

Of course, I could be wrong

R=V/I

Catchina, Thanks for the correction

Redwing, see?, I told you I could be wrong

qudos to Mchad

I fitted the LED position light to see what Canbus errors were seen and there were none!
So all this resistor malarkey is either car specific or a complete load of hooey

There is now a very intense and conspicuous white dot at the lower right of my headlamp bowl