Article HID Kit Relay Modification

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This modification should work on any of the bikes out there running a Bi-Xenon HID replacement kit. This is a very common design that is used by most of us running HID kits made by probably a couple companies in China sold under various brands. However because of variations in how the HID install was done and variations in kits out there it will cover a lot of theory and general ideas. Unfortunately this will make this a very long article without much for pictures. Sorry but I will need a thousand words to make up for the pics that would do no good. There are some different kits that use a Halogen high beam rather than the shields and while the HID/Halogen kit can likely be modified like this as well, I haven't seen how one of those kits is wired so I can't say for sure. Of course as always if you have questions ask and all modifications are at your own risk.

Backstory:
I have never been thrilled with something that I consider a critical system (headlights) having a single point of failure. When I see something which is poorly designed, failure prone or just plain old cheap. The goal behind this project was to add redundancy to the system so that if a relay were to fail, it won't take out both lights. There have been a few reported failures of either the relay or the connector of the relay. This change will address both of these. This also to replaces a proprietary relay which isn't readily available with one that is available from any automotive parts store or Walmart that you may come across on the road with a pair of relays to add redundancy. It also provides contacts which are much larger so less likely to overheat and melt. The end result is to make the replacement process easy enough that one can do it on the road if you wanted or there is a failure, you would have only lost a single light and you would likely still have more light output than a pair of OEM halogens. Initially, once I completed the change I had mentioned it to a few people but wanted to run it for a while to feel comfortable with sharing it. Then sharing this information became a problem with all the options out there. I have been running this modification now for a year and a half over about 14,000 miles without a hickup. So I feel that it should work for anyone out there.

So enough of the backstory on this. I will be working on this article based on feedback so it will be a living document. If people see places to improve it, or changes to address a certain HID kit that I haven't worked with please share and we can improve this.

What you need:
There isn't anything special, it all can likely be sourced from a single trip to a local hardware store or automotive store. I will provide web links so you can see an example of what I am talking about. They may not be the best price but just the first thing I found on a search of Amazon for simplicity.

2 x Relay Sockets - you don't have to have these but they make a swap easy to do.
http://www.amazon.com/Parts-Express-5-Pin-Relay-Socket/dp/B0002ZPUMG/ref=sr_1_2?ie=UTF8&qid=1369515724&sr=8-2&keywords=relay socket&tag=vglnk-c786-20

2 x Bosch style 12v Relay - Bosch or clone 30A or 40A deosn't matter. I have used them all and never had an issue.
http://www.amazon.com/RELAY-BOSCH-30AMP-SPDT-12V/dp/B001JT016Y/ref=sr_1_1?s=electronics&ie=UTF8&qid=1374329150&sr=1-1&keywords=bosch+12v+relay

I prefer to make all my connections by soldering and using heatshrink. Others use crimp connectors or one of the various options. Out there. Soldering is what I do, do what you are comfortable with. Since I have the soldering supplies on hand all the time I didn't need anything else further. If you are doing some other method you will likely need quite a few connectors. I am not going to give a count for sure but 20 should be good.

Volt meter/Ohm meter. This will be needed to identify wires as the HID kit runs everything through wire looms. It is good to have anyhow if you don't own one. You don't need an expensive one. A basic one will work.

Theory:
All of the kits I have seen are wired about the same. Basic theory is that you have a power wire direct from the battery going into the relay. There is a ground wire. You have an output going to the hot side of each ballast. Input for high and low beam from the H4 socket on the bike then output to high beam on the bulb. I think the ground for the high beam comes back to the relay. Maybe someone could confirm this. Remember I said this is a living document.

As I go through the wiring process I will refer to the numbers for the connection points on the relays. This is because the sockets don't use standard colors between all of them out there but all relays (Bosch or clones) use a standard number identification pattern. These numbers will be 30, 85, 86, 87 and 87a. 85 and 86 are the coil side of the relay so they are the trigger. 30 and either 87 or 87a are the connection for what is being switched. The load side depending on if you want it hot when the coil is active or not. Standard relay stuff.

I recommend using the relay sockets because it will make life easier to wire this up. They are also keyed the same way as the relay so if you are trying to swap a relay in the dark, it will only fit one way and the replacement will be properly connected no matter if you remember how you wired it or not. If your relay sockets have 5 wires it is best to pull one of the wires from each socket. It is the wire which is in the middle of the socket can come out. This connection point is called 87a on the relays it may or may not be labeled on the socket so I typically look at the numbers on the relay and line them up with where they would go in the socket. This is the connection that would be hot from the battery (which will go in 30) if the switch (coil between 85 and 86) is dead. There really are not many applications where you would want to use 87a (switch off but device hot) so it is common to remove this and why you can find relays without this connection if you shop around, though it will limit your options of a replacement on the road if you are in a pinch. If you don't pull it the wire will be hot when the system is off so you need to properly protect it. Sockets might differ but typically if you insert a small flat screwdriver along the side of the wire into the socket you can release the connector and pull out the wire. It might take a small eye glasses screwdriver or something of the sort.I pull it out so I don't have to worry about it shorting out on anything. Alternatively if your Bosch Relay only has 4 conductors (the middle one missing) then you don't have to worry about it. However if on the road and you don't have a spare the wire could become hot if it were to be replaced with a 5 conductor relay. This is why I pull the wire. It gives me more flexibility and I don't have to worry about it.
There will be a few challenges here as there are multiple ways of hooking this up depending on how you did your HID install.

Lets get started:
First challenge.
Pin 85 on both relay sockets
Lets get the hard part out of the way first then we can do the easy stuff later. Really this first part is going to be by far the hardest part of the process. This has to do with how the Kit's relay knows to complete the circuit going from the battery to send power to the ballasts. In theoriginal form it looks for power on either the low or high beam wires on the H4 socket. The problem is that there are so many ways (TDR, manual switch, sidestand switch, leaving it stock, ect) of hooking up the HID kit that I don't know how your bike is wired. We need a way to tell the new relays to turn on no matter if high or low beam has power. So tieing into the H4 socket for this isn't that easy without some circuitry that I doubt you could buy off the shelf and wouldn't be easily replaceable or redundant. So how do we get power to trigger the new relays on pin 85? Well lets look at a few installations out there.

TDR installation:
If you have a TDR installation as outlined in the following article here. https://www.st-owners.com/forums/showthread.php?97702-HID-Install-with-Time-Delay-Relay
I am starting here as this is the way my bike is set up. In this case I taped into the wire that comes out of the TDR L connector that also has a connection to the rocker switch when on bypass mode. If you go to the diagram in the link above it is the blue/white wire. Because this is done before the bike splits the circuit between high and low beam it is the best place to get power to turn on the ballasts. It also will retain the function of the TDR and manual bypass switch.

Manual switch installation:
If you followed basically the directions that I provided in the TDR install but went with a two position switch (on/off) wired the same way as done in the TDR install you can tie into the splice point with the blue/white wire like mentioned above and get the same result.

Police Switch installation:
You will need to figure out which wire is the output on the headlight switch. It will be basically the same installation as outlined in the manual switch. Splice into it so that it still is connected to the bike's harness and also runs to the new relays.

Sidestand Switch Relay:
I haven't actually looked into this that hard so we will need to improve on this one with feedback. There is something that you would have done to prevent the HIDs from firing until the sidestand is up. Is there a relay on the 12V source from the battery? If so follow the recommendation for no special wiring which is the next section. If it was done through some other means we may have to discuss. PM me or respond in this thread and we can talk it out.

No Wiring Changes:
Some people are holding the start button down as the turn on the ignition. You will need to splice into the Blue/white wire as outlined in the TDR relay. I would do it on the switch pod side of the harness.

Pin 30 on both relay sockets.
Time for a fairly easy one. This is going to tie into your fused wire from the battery. This wire on most kits is the heaviest gauge red wire. I can't say for sure as it depends on the kit. Trace the wire to be certain. Since this is a constant hot it will be a live wire unless you pull the fuse or disconnect it from the battery while working on it. As mentioned tie to to both relays.

Pin 87 on both relay sockets.
This is the connection that will send power to the ballasts. Unlike before you don't want to tie these wires together. The wire from one socket will go to one ballast. The other wire from the other socket to the other ballast. This way if a relay fails we would only lose the ballast that is connected to that relay and half your light output until the relay is replaced. Though failures will be extremely rare. If I were to guess at which wires I am talking about, typically I have seen two separate wires with separate connectors with the HID relay. They are typically the two next to the main power input from the battery but trace or test the wires to be sure.

Pin 86 on both relay sockets.
Now things are getting easier. Run these to ground. Doesn't matter how you installed your kit. This is the ground side of the coil on the relays which is used for switching the power circuit. You will have a couple more wires going to ground so be prepared for that as we move forward. I just wanted to wrap up the last of the connections to the relay sockets.

At this point if you haven't done so already the relays can be installed in the sockets. I would label them (L or R) and place them somewhere you can get to. Mine are zip tied to the bar where the stock horn mounts under the right inner cowl. I carry enough tools to get the inner cowl out so that works for me.

Addressing additional ground wires. There should be 4 more black wires (may not be black) going into the connector to the original relay. Two of them are the ground wires coming back from the ballasts. In all cases I have seen they are the same gauge as the wires that run to power the ballasts. They can be tied together along with the pair of really thin ground wires (black) from the bulbs. These thin wires are ground from the circuit to enable/disable the electro magnet that moves the shield for High/Low beam.

Remaining wires.

Thin red wires:
We still need to send power to the electro magnets in bulbs. These are the thin gauge wires, typically red, that run directly to the bulbs. The way it works is when the bike is in low beam mode. The 12V wires are dead and the electro magnet at rest held in place by a spring or something in the bulb with the shield blocking some of the light. When you flip the high beam on it will send power down one of the wires on the H4 bulb and energize the electro magnet which is strong enough to overpower the spring and pull the shield out of the way. This allows more light to hit the reflector and throw more light out ahead of you. This is why we didn't want to simply cut the blue/white wire way back when we were doing the hard part where we needed to provide switched power to the pair of relays we are adding. So since the high beam wire coming off the H4 plug is fused and already on a relay (bike's OEM harness) you can identify which wire is hot when the high beams are on (volt meter) and tie that directly to both of the small high beam wires that run to the bulbs.

The only two wires we have left at this point are the low beam power wire from the H4 socket and the ground from the H4 socket. The ground can be used for your ground connections that you were making above. The low beam wire should be protected and tied off. It isn't needed for anything but it needs to be protected as it will be hot when the bike is running and you have your low beam on. It wasn't used in anything as it isn't hot when the high beams are on and not of use for us.

Here is an example of how the H4 socket should be wired for identifying those wires.
 

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Joined
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Being the first to reply, I want to Thank You Very Much for doing this.

Your starting to get to know me, I like to analyze till I'm paralyzed, I also don't like to go back in on a project and correct the small things that can bite you in the rear later.

Al
 
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sennister
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moddy

the mod
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Really, it just exemplifies how out of the ordinary I am, and unnaturally hard it is to bring clarity. I think I did a search that brought me to the much more in depth discussion, THEN, I saw the post on relay modification. I will read more of the thread you posted on July 20th, when I get a chance. I want to get those HID's in there.
 
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