LED Tail light and Rear Light Monitor Light - K-Bikes.com - Excellence in Motion
 
LinkBack Thread Tools Display Modes
post #1 of 4 (permalink) Old Dec 19th, 2012, 5:44 pm Thread Starter
Member
 
Join Date: Dec 2012
Location: York, PA, United States
Posts: 106
LED Tail light and Rear Light Monitor Light

I converted my 85RS to a scrambler. One change was the replacement of the stock tail light assembly with a LED running/brake/license light combo. My issue is the rear light monitor light in the instrument cluster won't go out when the front and rear brakes are used. I am guessing the LEDs aren't drawing enough power. I can always pull the bulb, but I like that monitor. It has drawn my attention to rear light problems many times. What is the solution? My knowledge of electronics is limited. I can do very basic soldering; so, I could put a transistor of some sort on one of the rear light wires if I knew which wire and which transistor.

++++++++++++
Jon
97tiger885 is offline  
Sponsored Links
Advertisement
 
post #2 of 4 (permalink) Old Dec 21st, 2012, 7:53 am
Addict
 
Join Date: Mar 2004
Location: , , UK
Posts: 3,750
Yours is a common problem with vehicles that have a bulb failure monitor when led lights taking very little current are fitted. The simple bulb failure circuit monitors the current flowing through a good bulb and that keeps the fault light out.

At its simplest level, one solution is to fit a resistor across the led light so the bike thinks the bulb is still there. These monitors can work in different ways. The most difficult is the system that needs to see the full bulb current to keep the light out. You would need to get a bulb of the same wattage and wire this to your led rear light which somewhat defeats the object. You could also use a resistor with a big wattage but that will get hot!

Often these circuits will put off the warning light when a current less than the bulb rating is present. How much less depends on some tests you would have to do first. Find out the wattage of the rear bulb you took out, then try adding a lower wattage bulb across your led light to to find out the LOWEST wattage that can make the warning light go out.

Lets say you find a 6 watt lamp would turn off the warning lamp. You could then go buy a 30 ohm 6 watt resistor and wire that to your rear lamp wiring and mount it somewhere where it would not burn anything. If a 12 watt bulb turns off the warning, then you would need a 15 ohm 12 watt resistor etc.

These are the type of high wattage resistors to use which can be fixed to a flat metal surface somewhere on the bike.

http://uk.rs-online.com/web/p/panel-...stors/1073188/



Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!
voxmagna is offline  
post #3 of 4 (permalink) Old Dec 22nd, 2012, 7:47 am
PsyKotic Waterfowl
 
Join Date: Aug 2006
Location: Seattle, WA,
Posts: 1,328
Putting in a load resistor in parallel defeats the purpose of having a bulb monitor because it will always "see" the load resistor as a good filament. Also, for the taillight, since it is always on, the load resistor will need to be mounted somewhere where it can dissipate the heat that it generates. Even though the bulb monitoring feature will be disabled, the testing of the two brake switches at startup will probably still work.

I run all of my Ks with LED brake and tail lights. My solution, since LEDs last "forever," is to just get rid of the bulb monitor altogether. At it's connector in the left side of the relay box under the tank:

Short the front brake switch wire(Gray/Red) and the rear brake switch wire(Gray/Green) to the rear brake light(Gray/Yellow.)

Short the tail light power(gray/white) to the tail light wire(Gray/Black)
FlyingDuck is offline  
Sponsored Links
Advertisement
 
post #4 of 4 (permalink) Old Jan 16th, 2013, 3:04 pm Thread Starter
Member
 
Join Date: Dec 2012
Location: York, PA, United States
Posts: 106
Quote:
Originally Posted by FlyingDuck
I run all of my Ks with LED brake and tail lights. My solution, since LEDs last "forever," is to just get rid of the bulb monitor altogether. At it's connector in the left side of the relay box under the tank:
Thanks for the tips. I am back on the road after replacing the plugs and fuel pump relay. I finally decided to pull the bulb on the dash. About 10 minutes of work. Now I need to break myself of the habit of hitting the front and rear brakes on start up.


++++++++++
Jon
97tiger885 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the K-Bikes.com - Excellence in Motion forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Absolutely the most detailed description of the K1200S I've come across... sinc K12/1300S 20 Jul 19th, 2014 10:04 am
18K Service - How many hours? Captain K12R K12/1300R/R-Sport 8 Jun 17th, 2011 12:18 pm
Road Rocketeer LED tail light budcarrigan K12/1300S 6 Nov 7th, 2009 8:47 am
ECU Rear Light KPower K12/1300S 4 Dec 26th, 2007 6:13 pm
Clear front turn signal and tail light lens kits pebo K12/1300S 24 Apr 20th, 2007 4:47 am

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome