Brake light question
Seasoned HDF Member
Joined: Mar 2010
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From: Honah Lee
Harley has a plug and play block that goes in at the seat connection. Just replace amber lens on thoes with red if necessary. It's basically just diodes with adapter plugs. Like the boat trailer adapter for cars with yellow signals and a red signal light trailer.
Seasoned HDF Member
Joined: Mar 2010
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From: Poolville
A friend of mine had one of those boxes to convert taillights into turn/stops and we were away on a trip upstate..His battery kept kept dying every 100 miles.. Finally after the 3rd time I told him get rid of that thing.. We pulled it out and just ran regular lights. Sure as **** it was shorted on the inside creating a constant short on the battery somehow.... I would never use one of those...
Seasoned HDF Member
Joined: Mar 2010
Posts: 38,586
Likes: 6,435
From: Honah Lee
A friend of mine had one of those boxes to convert taillights into turn/stops and we were away on a trip upstate..His battery kept kept dying every 100 miles.. Finally after the 3rd time I told him get rid of that thing.. We pulled it out and just ran regular lights. Sure as **** it was shorted on the inside creating a constant short on the battery somehow.... I would never use one of those...
I have installed a few on Toyota's trucks. Set up a rig the owner brought me and new signal lights. Had it all set and just to be sure, checked the truck at the trailer plug and all good.
Plugged it in the harness for the trailer lights I had installed and it didn't work. Unplug it and checked back at truck. Nothing at harness or truck tail lights. Nothing. Checked the truck fuse and found two blown. Fixed that and had tail lights but still nothing at harness from the diode box. It was toast.
Check the trailer and one positive wire was grounded. Pulled the new trailer light and removed the lens. China man had accidentally put one of the positive wires under the ground plate.
So it's real easy to fry a diode . They are one way circuit. But too much load takes them out like a fuse. Or if they short but don't burn out like they some times do in a voltage regulator let AC come thru from the alternator rather then changing it to DC.. Modern system prevent damage. Older stuff can be wrecked by AC.
What you said about draining a battery will do that if an voltage regulator goes bad since the system is hardwired thru. The block from battery back to alternator is the diodes.
When running, of course AC comes thru that direction as DC.
What you described however puzzles me since normally, that block only gets a voltage if it from lights, brake or signal when bike is on and running. So it should not drain battery.
Seasoned HDF Member
Joined: Aug 2007
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From: NW AR
A friend of mine had one of those boxes to convert taillights into turn/stops and we were away on a trip upstate..His battery kept kept dying every 100 miles.. Finally after the 3rd time I told him get rid of that thing.. We pulled it out and just ran regular lights. Sure as **** it was shorted on the inside creating a constant short on the battery somehow.... I would never use one of those...
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Seasoned HDF Member
Joined: Mar 2010
Posts: 21,115
Likes: 7,638
From: Poolville
It was somehow back feeding voltage through the lighting ground systems not enough to blow a fuse or trip a circuit breaker but enough to draw the battery down where it would not charge... All I know is once removed we never had another issue...
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Dirt don't hurt
Joined: Jan 2011
Posts: 21,065
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From: Haslet Texas
Something tells me that Harleys unit won't be compatible with EVO era bikes.
