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Tapping 12v off the diagnostic plug

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Old Mar 30, 2017 | 05:17 PM
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Default Tapping 12v off the diagnostic plug

I got my Love Jugs Mighty Mite in today.
Once installed I went to hook it to the accessory plug located under the seat.


Accessory plug (thought)



Turned on the ignition and nothing happened.
Confirmed with Steve at Love Jugs that there is no type of thermostat on the Mighty Mite so my problem was either a defective unit or my accessory plug wasn't getting power.

I checked the voltage at the accessory plug and found that the 12v pin on the plug didn't match up to the 12v pin on the Love Jugs connector.


Love Jugs connector



After much research I've pretty much figured out that what I thought was the accessory plug must be the ECM diagnostic plug and that I have no "Deutch" accessory plug.

So my question, would it be any harm to tap into the switched 12v wire of the ECM diagnostic plug or should I just find another switchable power source?
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Old Mar 31, 2017 | 10:49 AM
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That's the diagnostic plug. My 2 cents is not to use that to power any accessories.

I would tap directly onto a switched power source with a fused line with the connector you need for the accessory wired correctly to match.


Mike
 
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Old Mar 31, 2017 | 11:04 AM
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Originally Posted by Mike NY
That's the diagnostic plug. My 2 cents is not to use that to power any accessories.

I would tap directly onto a switched power source with a fused line with the connector you need for the accessory wired correctly to match.

Mike
Thanks Mike your recommendation is pretty much what I had figured I would be doing but I thought I'd ask to see if others had tapped into the ECM power with no issues.

Any way, I'll just tap into another orange/white wire with a fuseable link and let it be.
 
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Old Mar 31, 2017 | 09:28 PM
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I have the same quandary, I am using the front switchable plug to power my LED driving lights and GPS. I need to find a switchable source under the seat. Some Softy's have a plug for a rear fender light. Either that (if I can find it) or tapping into the rear tail light.

Any other ideas would be muchly appreciated.
 
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Old Apr 12, 2017 | 10:02 PM
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Originally Posted by Mike NY
That's the diagnostic plug. My 2 cents is not to use that to power any accessories.

I would tap directly onto a switched power source with a fused line with the connector you need for the accessory wired correctly to match.


Mike
Why not? Harley sells an adapter that plugs into the diagnostic plug with pigtails coming out for just this purpose.
 
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Old Apr 13, 2017 | 07:24 PM
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Originally Posted by Jimmy55TX
Why not? Harley sells an adapter that plugs into the diagnostic plug with pigtails coming out for just this purpose.

I didn't know that.

I like to have any accessories powered thru it's own fused power source but I guess it's doable then...


Mike
 
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Old Apr 13, 2017 | 08:31 PM
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Originally Posted by Jimmy55TX
Why not? Harley sells an adapter that plugs into the diagnostic plug with pigtails coming out for just this purpose.
This is the best way to go. $20 harnnes, plug and play and gives you switched and unswitched power leads. 5 minute hook up once the seat is removed.
 
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Old Apr 13, 2017 | 10:03 PM
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I tried tapping into an accessory line last year on my 2014 Slim... All it did was fudge with everything and throw error codes. All I was trying to do was install some non CANBUS compatible auxilliary lights

I picked up the proper accessory plug harness as described and tapped into that wire. Worked perfectly after that! I was so happy when somebody showed me that part! I'd been fighting with these lights for a couple weeks.
 
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