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Need a switched power source for a 2-plug 2a USB outlet, 88 K75 non-abs

xp8103

New member
Picked up a dual plug 2A Oxford power outlet, mounted to the dash pad on the bike for a GPS and phone charging, neither big power sucks. But the outlet has a nice blue LED in it that is illuminated when the power is on. So it needs to be switched power. My knowledge of electrics is just enough to make spark and smoke but I know this is not a difficult issue. There are a couple of switched sources in the fuse box, one I'm fairly certain is the security system (not so equipped) and the other is... Heated grips (also not so equipped but may be someday)? One is white female and one is larger black male. Both have a switched 12v source but the wire is light gauge compared to the power lead to the outlet.

There is an old thread here that talks of having the GPS power on all the time so that you aren't constantly prompted to turn it off or keep it on every time you shut the bike off. Our DL650 came with the Zumo 550 on switched power and I do understand the issue. My other thought is to use a stock BMW aux rocker designed for the dash pad. Motobins has them for relatively easy money, one 2-position with a blue light when on.

The question is can I run the power thru the switch directly as opposed to hooking in a relay somewhere in the line (perhaps back in the fuse box)?
 
The easiest place to tap switched power on that bike is the tail light circuit which can be accessed under the seat.
 
For low power-draw items, you shouldn't need to run thru a relay.
Since your new toy is going to be dash mounted, I see the appeal of using a blanked off dash switch. I know I be tempted to go that route.
I'd also second Paul's suggestion on the ease of accessing the taillight circuit under the seat for a switched power source.
 
I did a three connector panel on my 2003 K1200GT.

Check eBay for your items. Searching for USB dual outlet 12vt. I think I paid $12 or so for the triple power outlet

https://www.ebay.com/itm/Linkstyle-...921113?hash=item340566c719:g:V88AAOSwvmxceNIj

https://www.ebay.com/itm/Dual-USB-C...056929&hash=item2612350e16:g:m6sAAOSwAaxcUFOE

From advise last summer from others, there is a Green wire to the rear tail light that is ON when the key is turned. See the picture of my red wire tap I added on that green wire.

In many ways, I agree with Jeff that you are 90% ok with your low voltage to just use the green wire as your positive and find a solid negative ground from the frame. Task done. Simple solution, worry about blown fuses, code warning, should or if it happens. In that case, plan B.

A safer way and more robust method is to use a relay. Do a search on "12V 40A 5 Pin Waterproof Integrated Relay and Holder Electrical Connector" and you will see some. Mine is a little too large (2x"3") for my tool box space, but there are some micro ones (1"x1") sized out there. Typically they have 5 wires, battery pos/neg, trigger wire positive from taillight, and then output you new USB pos/neg. Not too hard, but gives you the right combination of full power and isolated from the bike.

Relay
https://www.ebay.com/itm/Waterproof...332928&hash=item21238efe73:g:wJIAAOSwDXFceIMu

Sorry no picture for you, but two wires from my battery to the relay, two wires from the relay under the tank to the center of the fork. Connectors there to the USB and voltmeter. A 12vt cigarette outlet at 22amps, two usb at 1 and 2amp. A fuse from battery to my reply is set at 10amp as my battery max is 22amp. My Garmin and Cellphone only draw 2a total and the dash camera another 2 amps.

I haven't used the cigarette lighter connector, but I do have LED fog lights attached to the two wires out of the relay. Adding those fog lights, puts me into the Relay solution as best practice. Someday, I might add more LED lights to brighten up visibility.

What I find a problem is all the new wires, I am adding. Wires to the fog lights, wires to a triple connector, space the reply eats up. Over time, I will simplify and find smaller wires to accomplish the same task.

Warning, the Key on startup diagnostics process sometimes flags a warning error code on the tail light. It noticed the extra amp to trigger the relay. Using the diagnostic tool GS-911, I saw it on my bike. Since I have that tool, I can clear it. Don't let anyone charge you $$$ for clearing a warning code that the internal computer noticed. It does not affect performance or shut your bike off on the warning code.
 
pictures of the green wire, I think the pictures dropped off. Here they are.
 

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Thanks all. I think given Jrmull's assertion that he's drawing a total of 2A for both phone and GPS, I'm going to go with dash pad rocker switch and run the power thru it. That is the simplest way. In that way my wife can leave it on during short stops for gas and such but the blue light will remind her to turn it off when necessary.
 
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