Headlight Control by Start Switch

DEcosse

If it's no Scottish it's CRAP!
Joined
Jun 8, 2011
Messages
2,026
Location
Bay Area, CA
Ride
Triumph Daytona (Custom)
I just created a new Module to control the Headlights, used in conjunction with Ignition Switch BYpass Headlight Relay Kit.
The neat feature of this is that it gives you full manual control to turn the headlights on or off at any time - without actually having to mount an auxiliary switch for that function: it uses OEM the Starter Switch as a trigger to turn both on or off. The additional bonus is its location being right at your thumb, no need to remove your hand from grips to operate.
(I hate having to mount non-std switches on the bike - my KeyLess Ignition is similar in that regard, where it also utilizes OEM switches to enable it; there's just nothing that looks great IMO)

Recognize that the starter ONLY runs when BOTH the Starter button is pressed AND the clutch lever is pulled - you can press the start button by itself (without the clutch) and absolutely no action takes place with regard to any OEM function, most importantly the starter itself will not run! And we will never normally utilize the start switch for anything other than starting, so that makes it freely available for use as a control-trigger.
So this is the signal we are going to utilize to turn the lights on or off.

The circuit is actually a small PIC Microprocessor that will simply toggle the output control function to its opposite state, when the start button is pressed each time. i.e if the output is high, it switches low and vice versa.
This is then fed through a driver to the relay coil, to either enable or disable the relays. It does not matter whether on Hi or lo beam, the headlights will be on or off accordingly, with only one module required to control both.

Even if bike has not yet been started, note that the lights will not come on when you first turn on ignition; but then if you need them on without starting, just press the start switch (no clutch!) and they will come on; then if you decide to start anyway, as soon as you engage the clutch and start switch together, the starter will run and additionally, the OEM cut-while-starting will still function, turning them off once more to ensure maximum energy for starting.

The circuit consumes extremely low current and is only switching ~ 140mA for the relay coil; even that current is not being provided by the controller's on-board 5V supply, it is coming from the main headlight power, simply 'sinking' to ground via the controllers output device. All the 'heavy lifting' of the headlight current is being done by the power relays used for the Ignition Switch Bypass.


This is my complete plug n play Headlight Relay Kit with Start-Switch Control

Headlight_relay_Kit_w_startSw.JPG
 
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@DEcosse
Ken, can my PDM60 system you are making be made to do this?
I'd like to eliminate the EB bar switch?
 
You can actually make this work with an EB kit to replace that system's manual switch (which only works on low beam as you know)
It would require some rework (it does not connect electrically in same place as that manual switch) but it's doable
Nothing we can use with the PDM60 - there aren't enough switchable channels with that to utilze one more (you're already going to using your one negative switch channel for your auxiliary lights

Also not, it does fit nicely on the face of the relays I use - and requires connection to those relays and also to the starter relay - although it can be mounted anywhere really, and you can pick up same signals off the front end.
 
You can actually make this work with an EB kit to replace that system's manual switch (which only works on low beam as you know)
It would require some rework (it does not connect electrically in same place as that manual switch) but it's doable
Nothing we can use with the PDM60 - there aren't enough switchable channels with that to utilze one more (you're already going to using your one negative switch channel for your auxiliary lights

Also not, it does fit nicely on the face of the relays I use - and requires connection to those relays and also to the starter relay - although it can be mounted anywhere really, and you can pick up same signals off the front end.

That pretty zinged over my head even after three readings. :laugh:
Can it be added on your end with connections and direction - if so, let me know the $$$.
 
Very good, D%^n near genius. An Idea for you, is there a way to add circuitry to say cause your system to flash lights off and on for day light driving or perade mode? Their seems a good potential here.
 
is there a way to add circuitry to say cause your system to flash lights off and on for day light driving or perade mode?

You mean hazard flashers?
Those would be unrelated to either the KeyLess or the headlight Bypass but it's REALLY easy to do - the info is a freebie for you guys.
All you need is a switch of your own choosing and a couple of diodes.
- if you get something in a switch that is really miniature you can possibly mount it directly on your OEM switch housing and the diodes inside - but it's OK to go with an external switch if you prefer (easier to execute)
The switch needs to be a regular switch, not momentary one.

So just three components - 2 x 3A diodes and a switch; note my schematic shows the connections on the main harness side of the bar-switch connector, but these can be made on the bar-switch side or even inside the switch housing.
For those who like numbers, each diode will be supplying front& rear light on one side - total 20W - that is ~ 1.7A, so 3A diode is well safe.

e.g.

(It shows Bonneville on the diagram but is same for Rocket3)




Connect the two diode anodes (end without the stripe) together and to one terminal of the switch, connect other end of the switch to the Turns Input signal (Lt Green/Brown on Main Harness, Orange on Left Switch harness); then connect each of the cathodes (end of diode marked with stripe) to each side's turn signal

images
 
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Hazard lights is one concept but how about on the duel head light on the roadster flashing left light on/ right off and then reverse. using the start button like you have it turning the light off/on, but say pushing the button and holding it for 5 to 10 seconds to activate it. I understand the circuitry just not programming. Again this is fantastic information.
 
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