Solved - Top Box Lighting Wiring

[t-willie]

I have an older Bestem Top Box on the ST1300 I bought a few months ago. The light has never been wired. I bought a Bestem quick release harness but it is for a newer model box. I am wondering if I can make the harness work and how. I am attaching some pictures and would appreciate any help. If I can't use the harness, how can I just wire direct? Is the light on the box supposed to be a brake light, running light, or both?

1. These are the two wires from the top box.
2. Picture of black wire from harness split into 2 wires.
3. The 4 wires from the harness. Red, yellow, white, and black where it splits to 2.
4. 4 wires at end of harness that should wire to bike wiring.
5. 2 plugs to brake lights.
6. Top box

Thanks in advance.

 

[GGely]

Hi t-willie, a few questions:

1. To confirm, picture 1 is of the wire coming from the top case? How long is this wire from where it exits from the top case?

2. Pictures 3 and 4 are of the harness that you bought to wire it up? There are no other components to it?

3. I’m assuming the two connectors that you show in picture 5 connect to the terminals of your existing brake light modules? I’m not familiar at all with the ST1300, unfortunately. The wiring diagram I checked has slightly different wire colours but if they do connect to the brake lights, that will be helpful.

On the other hand, I have a little business doing bike electrics so I should be able to help you on this one.

LED bulbs (which I’m assuming they are using in the top box) are directional in the way they connect, so we need to know which wire is positive and which is negative. The good news is they don’t care if you connect them backwards so trial and error testing shouldn’t cause any issues. If you’re comfortable doing it and the length of wire allows it, I’d put the box on the seat and touch the two wires to the terminals of those brake connectors, assuming that’s what they are. Based on the wiring diagram, the green wire with the yellow stripe and silver mark is the brake circuit. The brown and black wire with the silver mark is the tail light circuit, which leaves the green wire with silver mark as the common or ground connection.

Turn the ignition on, touch the blue and brown wires from the top box to the brown and black wire with the silver mark and the green wire with silver mark, respectively. If the light goes on, then the blue wire is positive and brown is negative or ground. If not reverse them. And note which grouping works.

Let me know how it goes.

G

 

[Andrew Shadow]

Mine is an older T-Box that has the separate upper brake light but the wiring harness seems similar. Maybe the Bestem wiring guide for mine might be of some help to you.
See the attached.

 

[GGely]

The connector John mentioned is called a Scotchloc connector in our neck of the woods and to his point, they are an awful way to do things. Here is what they look like: Scotchloc

If you’re not comfortable using a Western Union splice with solder or a variety of other methods, Posi Taps seem to be the least invasive method of getting a reliable connection without soldering: Posi Tap

Let us know how it goes

G

 

[ST Gui]

The connector John mentioned is called a Scotchloc connector in our neck of the woods and to his point, they are an awful way to do things.

They're called the same in my neck o' the woods and are just as awful. I too would rather splice and solder but th Posi-Taps are an invitingly convenient and reliable way to go.

 

[t-willie]

Wires located, spliced, and checked. Thank you to everyone for the great advice. Picture is of brake lights working. Just need to mount box back, put rear fender on and wait for the snow to melt so I can ride.

This forum is great because of awesome people willing to help.

Thanks again!

 

[t-willie]

There are a few videos on line - search 'Bestem Top Box Wiring'

They seem to suggest that it is an LED strip, that the red wire is +ve and you connect them to your brake wiring to give an extra brake light.

If you want it to be a tail stop light you can do that with a resistor and a couple of diodes for a few $. I have a link I can dig out on here to show you how.

https://www.st-owners.com/forums/threads/led-brake-light-convertion-to-tail-stop-light.147512/

For that you need to connect a third wire to the tail light +12v.

But first you need to verify whether or not any of those online videos relate to your tob box.

Got it working today. Thanks for your help.

 

[t-willie]

Hi t-willie, a few questions:

1. To confirm, picture 1 is of the wire coming from the top case? How long is this wire from where it exits from the top case?

2. Pictures 3 and 4 are of the harness that you bought to wire it up? There are no other components to it?

3. I’m assuming the two connectors that you show in picture 5 connect to the terminals of your existing brake light modules? I’m not familiar at all with the ST1300, unfortunately. The wiring diagram I checked has slightly different wire colours but if they do connect to the brake lights, that will be helpful.

On the other hand, I have a little business doing bike electrics so I should be able to help you on this one.

LED bulbs (which I’m assuming they are using in the top box) are directional in the way they connect, so we need to know which wire is positive and which is negative. The good news is they don’t care if you connect them backwards so trial and error testing shouldn’t cause any issues. If you’re comfortable doing it and the length of wire allows it, I’d put the box on the seat and touch the two wires to the terminals of those brake connectors, assuming that’s what they are. Based on the wiring diagram, the green wire with the yellow stripe and silver mark is the brake circuit. The brown and black wire with the silver mark is the tail light circuit, which leaves the green wire with silver mark as the common or ground connection.

Turn the ignition on, touch the blue and brown wires from the top box to the brown and black wire with the silver mark and the green wire with silver mark, respectively. If the light goes on, then the blue wire is positive and brown is negative or ground. If not reverse them. And note which grouping works.

Let me know how it goes.

G

Thanks for the advice. It is working. Yeah!

 

[fnmag]

Thanks for the advice. It is working. Yeah!

Glad you got it wired up. Looks good.

 

[GGely]

Nice!

G