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which tail light wire is switched power?

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11K views 13 replies 7 participants last post by  Brockie  
#1 ·
OK, I'm attempting to pull switched power for my GPS (I made my own cool little dash shelf to install it front and center above the tach and speedo) from the tail light. I heard that is the best place to get switched power. I checked the headlight wiring last night but it is so well encased in plastic wrap I don't want to start cutting into it. The tail wires are exposed and obvious.

A couple of questions:
1. How do you pull out the tail light assembly? I removed the seat and tools and looked back the "tunnel". Standing on my head I could see two Phillips headed screws that I could reach to remove -- but am afraid I'd never get them back in as I'd be working blind the entire time. So, do you work blind through the "tunnel" to take out the two screws or do you disassemble the back plastic some how after taking off the carrier? Not sure I want to do all that. It appears that the entire back plastic piece that houses the tail light actually starts at the seat and wraps all the way around to become the fender, all as one single piece. Ideas? Experience? Stories?

2. Which wire is switched power? Each tail light has a Gray and White-w-black-stripe wire, along with a Black-w-white-stripe wire. Based on the position of the Black-w-white wire, I believe those to be ground. Off to the left side are three crimped caps. One crimps together three White-w-black-stripe wires. One crimps together six Black-w-white-stripe wires. One crimps four Gray wires. By removing the plastic cap from the correct crimp, I can add my wire and pull switched power. There are also three different sized and colored 2-piece connectors. There is a larger Black plastic connector with a Green wire and a Black-w-white-stripe wire. The Green wire apparently is just passing through because I can't see it connected to anything. There is a slightly smaller Gray plastic connector with a solid Black wire and a Black-w-white-stripe wire. Almost out of play due to its position is a White plastic connector with a Gray wire and a Black-w-white-stripe wire. (I'm guessing the White plastic connector is for the license plate wire due to its location).

Once I get the tail light out of the housing, this will be easy. So the bigger question is, do you work blind through the "tunnel" to release it, or do you remove some tupperware for easier access?
 
#2 ·
It's the gray wire. Why go back there though? You can use the orange wire with a green stripe in the large connector inside the left fairing cowling. It's right in the area you need.
 
#3 ·
I was considering the tail light for switched power because I was considering adding a fuse box under the seat for things like my GPS and heated gear. Your idea would make a quicker path to the GPS for sure. I was just admiring that connector last night. I'll take another look. Thanks!

But I am still curious, what's the easiest way to release the tail light? I'll still need to know that some day for bulb replacement.
 
#5 ·
But I am still curious, what's the easiest way to release the tail light? I'll still need to know that some day for bulb replacement.
Those with small enough hands and good enough dexterity can reach in the back and twist counter-clockwise to release the bayonet mount. The housing with bulb can then be withdrawn. I have a couple of things mounted back there so need to take the fender off.

Remove the luggage rack with 4 bolts. Remove the two side bolts holding the fender to the rear subframe. Release the seat lock cable. At this point, I like to put a string with a bead on the end in the seat lock so I can get the seat off if I forget and put it on. The fender can be released with some cajoling as the plastic needs to be bent to clear stuff. Separate the wiring connector and remove the fender.

Image
 
#4 · (Edited)
That's what I did for my EB PC8... Couldn't be bothered fishing around for the tailight connector under the tank... just used a posi-tap on the gray wire from the tail light... Oh, and the rear tail light bulb assembly(s) just twists out about a half turn left... Right turn to re-insert...
 
#6 ·
Thanks for the exploded view of the tail light assembly. I'll have to check and see how far forward all the wiring comes by loosening the bulb holders. If the crimped gray wires come forward far enough to work on them easily, great. If not, I'll continue trying to get the tail light assembly (part #2 in the picture) out the back by removing the two screws. I really don't want to disassemble the whole back of the bike just to solder in a wire. Thanks!
 
#9 · (Edited)
Actually prefer to solder then shrink wrap. I believe it has less chance of coming apart over time. Vibration, etc...

But silly me, I thought the tail light housing came out the back once the two screws inside were released. I thought the red housing would fall out the back and I'd have access to those crimped wires. I just learned that is not the case. My logic is apparently not motorcycle designer logic. Apparently the housing comes out by going forward, but only once the rear end tupperware is taken apart. What the heck, I'm going to give it a try tomorrow night. It is winter after all -- time to learn since I can't ride.

Update -- OK, the tear down was easy. Fully removed part #3 in the exploded diagram above so I could work on the bench, took the crimp cap off the gray wire cluster, soldered my lead on, and re-capped the cluster. It's now ready to add a switched fuse box under the seat for my heated gear, inverter/charger and other plug ins. I'll use Greywolf's suggestion of the orange/green wire up front to directly feed switched power to my GPS.
 
#10 ·
Greywolf - That orange and green wire you suggest is in that big white 18 pin clip with 16-18 other wires. Is there an easy way to release the female portion of that particular pin connector from the 'battery side' of that 18 pin connector so that I can pull the orange and green wire and its attached female connector completely out of the 18 pin clip, connect my GPS power wire to it, and then put it back in the 18 pin connector? That's some pretty tiny stuff to be soldering on so I'd like to remove it from the clip for a better working situation rather than just cutting the wire further down the wrap and solder in my power cord. Thanks.
 
#11 ·
You don't connect to the pin. Connect to the wire. Solder wire to wire or use a Posi-Tap, not a Scotch-Lok.
 
#12 ·
Great info. I'm ordering an auxiliary tail/break light (think I'm going with this one here )

...and think I am going to go the posi-tap route, but doubt I will find them in a local store, so I am trying to figure out what gauge to order for the tail and break light if anyone has any idea what gauge they are.

Would really appreciate it. Also, any random advice/voice of experience from someone who has already hooked an extra tail/break light up, would be appreciated.

Thanks in advance.
 
#13 ·
I know this is an old thread. Is the orange wire with a green stripe in the large connector inside the left fairing cowling always hot or only when the key is turned. I want to tap into something that is only hot with the key turned to prevent parasitic draining.
 
#14 ·
Correct. It is the large plug left of the headstock above the radiator.
Others source the same power at the horn power wire. The orange/green wire turns to orange at the horn on many V-Stroms (not sure of your model V-Strom).

"Switched" power is always a wire that is live with the key on and dead with the key off. Also referred to as a "keyed" power source.

Another often used "switched" or power source is the heated grips connector. It is often hard to get to but necessary for high drain heated grips etc although most heated gear comes with wiring for direct connection to the battery.
Here are a couple of threads for different models