The Definitive Quartet Harness Farkle Wiring Guide
"How to power your first farkle"
I wrote this because there's always a lot of questions about wiring farkles and the quartet harness. Hopefully this will provide a starting point for most.
If you need to get power to a device on your ST1300 then this is the first article you should read. The reason is that there are choices to be made and everyone wants something a little different. Although there are plenty of threads on the quartet harness they are spread out and there always seems to be more questions about it. I think it's because most people don't know they should use or need the quarter harness and it can be intimidating to someone who just bought the bike.
So here's the outline:
1. Front End Power (Quartet Harness)
A. Description
B. Location (end to end)
i. Gaining access (fairing removal)
C. Connectors
D. Pinout
E. Installation
F. Mating Connectors
G. Power Options
i. Switched/Acc 12V
ii. Constant 12V
H. Connecting your device
i. Power wires
I. Conclusion
1. Front End Power (Quartet Harness)
The quartet harness is a Honda accessory that is used to supply power to power Honda accessories that can be purchased for the ST1300. If your ST1300 has the Honda 12V power connector in the fairing pocket, the Honda RDS Radio (available in Europe only), or the Honda heated grips then most likely the quartet harness was installed at some point to provide power to one or all of those accessories. If you still have a doubt as to whether you have the quartet harness or not you may be able to see it by removing the left inner cowl (6 plastic rivets and one phillips screw to remove). If you still can't tell you'll have to remove the left cowl (fairing).
A. Description
The quartet harness gets its name due to the fact that it has four connectors on the one end. Each connector is slightly different and each is used for a different purpose. Three of the four were designed for Honda accessories. The fourth has no known Honda application which makes it perfect to use for powering your own accessories.
The other end of the quartet harness has a 9-pin connector on it. This is how the quartet harness connects to the bike and how it supplies power to the four accessory connectors. It is fused with a 15A fuse that is located at the fuse box under the left side panel. There is a mating connector that is built into the main wiring harness of the ST to connect the quartet harness to the bike.
B. Location
The quartet harness is installed under the left cowling (fairing). The four accessory connectors are typical run up into the fairing just behind the head lamp assembly on the left side. There is a tubular support railing for the front fairing and the quartet harness is typically zipped tied along it until the support ends at the front left side of the frame. At this point the harness connects goes down and connects to its mating connector on the main wiring harness. The mating connector is located in a sheathed bundle with 3 other wiring harness connectors. This sheath is located just behind the left side of the radiator and is held in place by a rubber coated wiring retainer that is bolted to the frame.
i. Gaining Access
In order to gain access to this area you need to remove most of the left side of the bike. There is a good write up on removing the body panels on the ST1300 on this site.
http://www.touringmotorcyclists.com/front_faring_removal.htm
C. Connectors
As mentioned before there are 4 accessory connectors on the harness and one 9-pin connector that connects the harness to the bike. There 3 connectors with 3 pins and one with a 9 pin connector. White, Red, and Black are the colors of the 3 pin connectors. The 9 pin connector is clear. The 9 pin connector that connects to the bike is also clear.
The red connector is used for the 12V fairing pocket power outlet. The 3 pin clear connector is used for the heated grips. The 3 pin black connector is not used as far as we have been able to tell so it is available for connecting a low amperage accessory to (i.e. GPS, radar detector, etc.). It is also the ideal connector because it has constant 12V, switched 12V, and a ground wire. The switched 12V power is also available when the ignition is in the ACC (accessory) position. The clear 9-pin connector is used for the RDS radio.
So in review the black 3-pin connector is the best candidate to use because there is no preassigned Honda accessory that connects to it and it supplies the two main types of power including power in the ACC position if needed.
D. Pinout
If you want to power an accessory from a connector on the quartet harness then you'll first need to find power and a ground. Remember the quartet harness is fused at 15A. I do not recommend connecting anything to the quartet harness that pulls more than a couple amps. If you need more power than that consider going directly to the battery. Typically your device's manual will tell you the amount of current it draws or power it uses. If you divide the power (watts) by 12 you'll get the rough current (amps) the device draws. (power/voltage = amps). If all the amp, current, and power stuff is turning you on or is confusing you may want to check out the farkle primer I wrote that is available on this site.
Farkle/Accessory Wiring Primer
The pinout for the quartet harness is available on this site in the articles section.
https://www.st-owners.com/forums/showthread.php?t=7682
E. Installation
If you don't have the quartet harness on your bike it is not difficult to install as it only takes a few zip ties to put it into place. The bigger part of the job is removing the bodywork to get to access to the area in which it needs to be installed which is under the left side cowling (fairing). There is an installation guide available in the articles section on this site.
https://www.st-owners.com/forums/showthread.php?t=7714
There is also a good write up on removing the bodywork on this site.
F. Mating Connectors
Once you have the quartet harness installed you'll need a way to connect the power wires from your accessory to the harness. You could use wire taps but I don't recommend this method because they fail easily and are unreliable. There are vendors that sell the mating connectors for the quartet harness. They do require you to crimp pins to the power wires of your accessory and insert them into the mating connector. You can purchase the crimper needed from the same vendors that sell the connectors. If you are good and patient you can crimp the connectors using a needlenose pliers. Either way I recommend you order a few extra pins just in case. Once the pins are clipped into the connector you have a reliable connection that can be easily disconnected if you need to remove the device from the bike.
Here's a reliable supplier
http://www.electricalconnection.com/electrical-components/hitachi.htm
If you're going to connect to the black connector you'll need the 3-pin connector set which will include the pins.
If you need the crimper they also sell that:
http://www.electricalconnection.com/tools/tools-tools.htm
Once you have the mating connector you can decide which kind of power you want to use for your device, crimp the power wires for your device, plug them into the mating connector in the correct positions to mate to the power pins on the quartet harness connector, and plug the mating connector into the quartet harness.
G. Power Options
When connecting any device you have to decide when you want the device to be powered. Do you want the device to have power only when the bike is on or all the time. These two types of power are referred to as switched power and constant power respectively.
i. Switched Power
Most devices really only need power when the bike is on. This is referred to as switched power. The switched power on the bike is available on the green wire with black stripe on the 3-pin black connector on the quartet harness. I should also mention that the green wire with black stripe also supplies power when the ignition key is in the ACC position.
ii. Constant Power
However some devices like a GPS you may want to have power available to all the time so that you could plan a route while you're sitting in the parking lot and don't want to have the bike on to do it. This is referred to as constant power. Just remember to turn off any device you leave connected to constant power or you will eventually drain the battery. On the 3-pin black connector constant power is supplied on the red wire with green stripe.
If you use the black 3-pin connector the third wire (green) is a ground wire. The middle (green with black stripe) is the switched power wire and the red wire with green stripe is the constant power wire. All you need to do is assemble your mating connector and clip in the pins to match up with the power wire of your choice and the other pin to the ground wire.
H. Connecting Your Device
If you've read through all of this you probably have a pretty good idea of what you need to do. You need to have the quartet harness installed, purchase the mating connectors, crimp the power wires of your device to the mating connector pins, clip the pins into the mating connector to match up with the power line you want to use (constant 12V or switched 12V) and the other pin to the ground wire, and connect the mating connector to the 3-pin black connector on the quartet harness. That's it.
i. Power Wires
Most devices you want to connect are going to have a positive (power) and negative (ground) wire. You want to connect the positive to one of the 12V wires on the harness and the ground to a ground wire on the harness. The 3-pin black connector is the easiest for this type of application.
If you're not sure which wire from your device is the positive and which is the negative then look for a fuse. The fuse will be on the positive (power) lead of your device. The other will be the ground wire.
Use the pinout guide for the quartet harness to find a connector that suits your needs. Then find the wire for the power you want and a ground wire. Then get a mating connector, crimp the pins to your device's power and ground wires, insert them in the correct positions on the mating connector, and then plug the mating connector into the quartet harness.
I. Other options
There are other options for connecting an accessory to the bike but this is a good way to connect a device. You could go straight to the battery or tap off the switched 12V at the fuse box and use a relay. Both of those methods though mean running a power wire from the back to the front of the bike which is not always easy. You could also not install the quartet harness at all and buy the 9-pin mating connector that would connect directly to the connector that is on the bike wiring harness where the quartet harness would normally connect. You would have to use the pinout article to get the correct positions for power and ground to do this. All all valid options but I think the quartet harness is a good way to start out because it provides more flexibility in the future to connect other devices.
J. Conclusion
Hopefully this tutorial has helped you understand what the quartet harness is used for and how you can use it to connect some or all of your accessories. It is not intended for high power devices like HID or halogen lighting but it can be used for a GPS, radar detector, or other low power devices. With any installation make sure you understand what you're doing and take your time. There's plenty of people here to help so if you need it don't be afraid to ask.
Thanks,
Curt
