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Auxilliary Light Install KGT

Once the wiring connection to the light is complete secure the harness


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Wire bundle tucked in behind main lighting harness section so that it does not interfere with side panel installation


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Securing balance of harness so that it does not interfere with side panel installation


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Hi beam shut off

The schematic below shows how I control the Auxilliary lights via the Hi Beam Switch.

As stated earlier I routed all the voltage requirements thru my Centech panel.

If you do not have a fuse panel you can still wire as above except that you will need to add 5 amp fuse for the Normally Open relay - all details are next

Relay Function and Operation

The relay on the left is a NORMALLY CLOSED RELAY - meaning that when the relay is NOT ENERGIZED the contacts are in such a postion that there is continuity between points 87A (sometimes it is shown as 87O) and 30.

So that if you put voltage on pin 30 you will see that voltage on 87A - when the relay is activated the voltage that is on 30 is now disconnected from 87A/O and there is no voltage there.

By connecting the power that goes to the PIAA Switch thru the Normally Closed contacts of the relay you can control the PIAA Lights - when the high beam is off the coil is not turned on and the voltage signal reaches the PIAA switch and the PIAA lights can be turned on and off at the users discretion.

Now if the PIAA Lights are on and the high beam is activated there will be voltage on pin 85 of the Nortmally Closed relay and this activates the coil (becasue the other end of the coil is grounded).

When the coil is activated the Normally Closed Relay now switches from 87A to 87 - since 87 is intentionally not connected to anything the voltage signal going to the PIAA switch is now interrupted and the PIAA lights shut off.


The control for this relay is obtained from the hot side of the High Beam wire (Pin 85). Ground is attached to Pin 86.

When the Hi Beam or Flash to Pass (FTP) trigger is engergized it activates the relay and the control signal to the PIAA Switch is interupted.

12 volts is obtained from either the fuse panel or relay, a 5A fuse is placed in line to this line and it is connected to pin 30 of the Normally open relay.

Connect the orginal white trigger wire from the PIAA switch to the Normally Close (Pin 87A/O) of the relay.

The other relay is the PIAA relay and it is shown for reference only.


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Relay Used

The next two shots are of the relay I used and I got it at my local autoparts store


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Getting the Trigger Signal for the High Beam Cut Off

I did not even consider tearing into the headlight switch on the handlebar to pull the trigger signal, instead I went directly to the head light panel.

To gain better access and provide some room I removed the instrument panel.

It is very easy - it has 3 mounting points and one connector

Shown below in the Yellow Circles are the connection points.

The Pink Arrow shows the IP connector


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Here is a shot of the back of the instrument panel.

As you can see they are secured in a similar manner as the windshield bracket arms.

Also note the large washer for additional support to the post.


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Shown in the next two shots is the location of the headlight connector - Yellow Arrow


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Shown below is how I got to the point to acquire a trigger signal - the steps are as follows:

Disconnect the Headlight Connector from the back of the housing.

Cut the supporting zip-tie and pull back the connector as far as you can.

NOTE 1 - I could not pull it all the way out.

Cut back some of the cloth tape and access the WHITE WIRE

NOTE 2 - please verify the wire you are accessing if the bike you are working on is not a 2009 KGT 1300.

Open up the insulation of the white wire slightly so that you can attach a tie in trigger wire


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I attached a trigger wire and wrapped it around the exposed wire of the Hi Beam Line.

I used a black wire because I did not want to the trigger wire to stand out when dressed into the bike

I did not use a positap because I wanted a soldered connection - use what you want


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Connection insulated with some electrical tape.

Feel free to use heat-shrink or any other kind of insualtion media for the covering of the connection point - I only used electrical tape because I plan to over-wrap.


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Replacing the cloth tape with new cloth tape to revert back to orginal condition.

The trigger is now accessed, you can connect the head-light connector back onto the housing and give yourself about 3 feet of trigger wire as slack.

This portion is complete, now onto the PIAA Switch trigger wiring


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In the orginal PIAA Light install the trigger of the PIAA switch needs to go to 12 VDC - here we are going to tie it into a relay as explained earlier.

1 - Remove white wire of the PIAA Light Switch Trigger from Centech or battery - Green Arrow

2 - Create and attach a wire to solder to the white wire - Yellow Arrow - this will go to the relay

3 - attach a line to a fused 12 V source - on my Centech I selected a 5A fuse as this is a very low power signal - Red Arrow - this will go to the relay


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Shown here is the relay to control the PIAA light switch free-wired.

Shop tip - great testing opportunity before final dressing.​
Starting from the top:

Red Arrow is the 12 volt fused source - going to Pin 30 of the relay

White Arrow is the Ground connection - from battery or negative of fuse panel - going to pin 86 of the relay

Blue Arrow is the trigger signal from the Headlight - going to Pin 85 of the relay

Green Arrow is the line that was attached to the white trigger wire from the PIAA switch going to Pin 87A of the relay.


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Lengths of wires established - getting ready to final dress

Green arrow is identifying the trigger signal from the Headlight (Hi-Beam)


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