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Discussion Starter #1
'07 ST3s. In the factory manual wiring schematic there is a diode adjacent to the starter relay. I am asking for information about the specific physical location of that diode.

I've not been able to find it in the service manual's physical drawings or in the parts manual. Several searches here yielded numerous mentions of that diode but not its specific physical location. One post does suggest that it is "up in the wiring harness". ;-)

Thanks for any info & so sorry if it's here already & I just don't see it...
 

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Life is too short to worry !
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Not totally sure about the 07 ST3 but on my old '02 I seem to recall the Diode being located on the back of the starter relay so may be worth taking a look.
Surprised nobody more knowledgable has replied because i'm sure some have fitted new Diodes , maybe they'll chim in now.
 

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Discussion Starter #3
Gearbox, Thanks. I've actually peeked under the plastic cap on the relay & it appears the wires are directly soldered to the relay - but I'll be triple checking today.

Off topic. Absolutely one of the best weeks of my life was spent on an XT500 in Aberdeenshire - long time ago. Started & ended in Fyvie at a farm B&B. I'd go again for the Lady's breakfast alone. Corrieyairack Pass was as close to religion as I've been.
 

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It'll be there to prevent arcing in the relay to stop the contacts from pitting.

John
 

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Life is too short to worry !
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Corrieyairack Pass - Not one that I know but all the roads up here are fantastic for bikes and not too many traffic police around so can concentrate fully on riding instead of scanning the horizon and checking mirrors every few seconds.

John - Do you know the location was my recollection correct or should OP be looking elsewhere ?
 

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Discussion Starter #6
What are the forum rules about hijacking one's own question?


Been out for a ride. Back to the Duc diode tomorrow.
 

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Mr Leakered
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Whadya mean? Hijacking is an art form around here.

Nothing better than a tangent.

Have a good one.
 

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Ok !! Wont be taking my 4s on that bit of road......Looked great fun :)
 

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Was it the GS that couldn't keep it's panniers off the deck! the others looked like they could cope better.
 

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Discussion Starter #10
The diode in question is located in the harness 6 inches above the starter relay connector.

Disconnect the relay, disconnect pos bat cable, dismount 40 amp fuse holder, clip 2 or 3 zip ties, pull out harness bundle, slit first two layers of harness sleeve to expose leads to starter relay. slit starter relay sleeve. Thar she be.

A 10 cent part in a $900 wiring harness... buongiorno...
 

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It'll be there to prevent arcing in the relay to stop the contacts from pitting.

John
It's purpose is not as mentioned above. It's there to conduct the CEMF (Counter Electo Motive Force) spike that occurs when the solenoid is de-energized. This high-voltage "spike" can hurt sensitive electronics , if left unchecked.

(CEMF is basically a reverse-polarity transient spike)

Also, note that the older solenoids had them soldered to the solenoid/connector. Newer ones, sounds like they're in the harness!!
 
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