Hi everyone, I've ben searching for the forum for the past two days and been trying to trouble shoot on my own but I can't figure it out.

I have a 1982 seca xs400 that when I first bought I had running in the beggining of april, I've done a tear down and clean up of it and ready to start her up and now theres an electrical issue.

I went to start it and it blew the ignition fuse, and the diodode thats under the seat connected to skyblue and blue yellow wires. I checked over everything and I can't find a short, the fuse connections were cleaned.
The head light is only turning on some of the times when i turn the key, same with the speedo lights(the nuetral light turns on only half the time the speedo/tach lights turn one), and the turn signals are only working some of the times. I can get the engine to crank over but not fire only if i have the one relay disconnected, the silver color one, I'm not sure which one it is, but if its connected nothing will work and it will blow the fuse, so its acting like theres a short.
I changed handle bars, turn signals, and battery and thats it.

Any thoughts would be great, I'm running out of ideas here.

fuse box is more than likely corroded. I'd strip the harness and make a simplified wiring edition. The silver one is the blinker relay. should cause no harm at all. You definitely got an issue. Where do u live?

Okay well the signals and lights are definitely the fuse box, I will replace that. I figured out, I hooked up the relay and tci box backwards, ya stupid. Now most everything is working, I don't have everything like the signals attached and what not. But i wanted to crank the bike over, I'm not getting spark and the diode is still trying to fry off of the skyblue and blue/yellow wires, what is that for? Now I need some more suggestions.

I'm near allentown pa.

Well I'm still at a loss, I can't figure it out, I replaced the fuse box, the signals are still blowing the fuse and idk why, but the big thing is I'm not getting any spark, I checked the voltages at the tci for the coils and ground, they are a little bit lower than they should be like 11.3 when I guess it should be 11.5 BUT the voltage goes way down to 7.5 when I crank over, the battery is new and charged, I need suggestions please!!

bad v reg

I got a used rectifier off ebay from a "running" bike. After two weeks waiting for it I just plugged it in and the exact thing happens, a voltage drop of nearly half during cranking and still no spark. Now should I try the minimal wiring technique? Ugh Its mid way through bike season and this thing is still not running!

Hmmmm major short?, time to start checking all the wiring.....
Are all the grounds tight?

I will recheck all the ground tomorrow, could it be the pick up coils? Can I clean them at all?

If you'd get a diagram and a meter and sit down and figure this out methodically you would have had it fixed by now. All the guessing and "shotgun" repairs are eating your lunch.

True enough, I have the Diagram if needed...

I had the same problem and came across this post. I did not get any spark from my coils to plugs and the bike ran BEFORE I took it apart, (but I have another running XJ to look at and compare) so, a long story short I have a 4-wire relay (brass looking thing) that does not work. I switched it on the other bike and presto fired right up!
Now to be more specific, it is located under the tank (1981-82 Seca) it has 4 wires (red/wht, blue/wht, blk/wht, blk) on 1 bike there isn't any writing at all, on the other bike this is what it has on it:
4U8-00
OMRON
2081D9

I hope this helps you, and if anyone knows what this is, and where I can order one please let me know

Well it was the CDI/TCI, trust me I multimetered everything I could.
If any one else ever has issues here is what I found, my pick up coils both tested at 120ohms which by what I heard should be ~700. So I thought that could be the issue. my ignition coils tested 3.4 which was good. my relays were all clicking so I assumed they all worked. So once I got a new TCI it sparked right away but still had a voltage drop from 12.7 down to 8 but fires right up. I also did the turn signal relay mod to the 2 pin electrical relay, just like up the "L" terminals and you're in business.

Here is a pick of the finished product.
From this....


To this.

i29.photobucket.com/al...ril4th.jpg

no mufflers huh? i did that for about two weeks once.

dwcopple wrote:

no mufflers huh? i did that for about two weeks once.

Ya I'm going to try to make baffles for it when I have some free time tomorrow, it is way to loud and I really don't feel like dealing with the local cops.

how do you make baffles? I was going to try the ones from jc whitney for $6 each