Yamaha XS400 Wiring Diagrams

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To compliment my last post, here are the wire colors from the ignitor unit. As you can see, there are no solid black, solid gray, or solid orange wires here. For my application I’m going to try to match the wiring colors to those coming out of the ignitor unit since this will be a point of reference for future troubleshooting. The diagram shows solid brown, solid white, and solid green wires as an intermediary harness. I think that’s an opportunity to improve and save myself future frustration.
Going to contribute to this thread with a ledger sized and coloured 1977 XS400D Wiring Diagram.


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Hi all
I am looking for xs400 1980 wire diagram.
The 1981 says there is a head light relay.
Yet mine does not seem to have one. I’m confused. Can any one assist?
80 models has them at the front of the bike next to the neck under the gas tank.
That means some one took mine out and rewired the bike, talk about a pain lol. No worries will sort her out thank you for the information. I will be adding photos soon as I start assembling her.
This is a simplified wiring diagram the PO gave me with the bike. I verified it when I had to do work on the fuses. It says its for an '81 xs650 but it works with my '82 xs400 as well, granted the only stock electronics left on my xs is the ignition module. Just the bare bones basics. I've had the bike for close to 3 months now and I've put probably about 300 miles on it with no electrical problems except the occasional battery drain when left sitting. This might be a good resource for someone doing a compete rebuild and wants a basic circuit to get the bike on the road, or something along those lines.
In my quest to build my own wiring harness from scratch for my '78, I decided to translate the awesome ones on the German XS400.net site. I'll post the translated versions here if it's ok. Hopefully they will help anyone looking to do this. I also modified the one to include the three position light on/off/hi/lo switch included in on of the addendum's to the original drawings.
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Haven't seen much on the 1981 XS400H wiring diagram. Is it the same as the XS400SH? Trying to rewire this thing but I have no idea where to start

Edit: After a little digging, I found a thread on another site saying "The XS400 H (Special 2), SH & SJ (Heritage) US models share the same harness", so I'm guessing the wiring diagrams are probably the same
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$20 well spent on ebay


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