problem with lights

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Graham O
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Posts: 54
Joined: Sun Feb 05, 2012 1:28 pm
Bike(s): 1975 Honda ST70 Candy sapphire
Location: Norfolk
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problem with lights

Post by Graham O » Sat Jul 20, 2013 9:09 pm

Hi
I am having problems with the lights on my 75 st70, Does anyone know how to test the output of the lighting coil from the three wires coming out of it to the light switch (yellow pink and green) my headlight stopped working completely a week after mot from a restoration, I was only getting 4 volts going into the rectifier and the light switch seems to work fine when tested with a battery and headlight works, so I figured the lighting coil must be at fault so I have had it rewound and still no joy, I am wondering if maybe the flywheel is at fault but would like to test the output of the lighting coil before the headlight switch but not sure how to, any help would be much appreciated.
Thanks Graham

Chief
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Posts: 148
Joined: Thu Oct 06, 2011 9:27 pm
Bike(s): st-70 KLR-600
Location: Beverley,East Yorkshire
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Re: problem with lights

Post by Chief » Sun Jul 21, 2013 10:07 am

If your ignition is working I don't think it can be the flywheel at fault.
The 3 outputs- Green, pink, and yellow (C1-C2-C3 at lighting switch)are utilised as follows :-
Switch off -Green to rectifier connected to charge battery
Pos. 1 - pink connected to operate side and tail lights +charging
Pos. 2 - yellow connected for headlight + side lights +charging
This info may narrow your search for the problem
Check the output from these wires with a test bulb
Check the winding is grounded OK at the stator
Cheers,
Dave

Graham O
Standard Member
Posts: 54
Joined: Sun Feb 05, 2012 1:28 pm
Bike(s): 1975 Honda ST70 Candy sapphire
Location: Norfolk
Contact:

Re: problem with lights

Post by Graham O » Sun Jul 21, 2013 8:43 pm

Thanks Dave
I found the problem the guy who did the rewind had trapped a wire behind it when he put it back on the stator plate so it was shorting out.

Chief
Standard Member
Posts: 148
Joined: Thu Oct 06, 2011 9:27 pm
Bike(s): st-70 KLR-600
Location: Beverley,East Yorkshire
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Re: problem with lights

Post by Chief » Sun Jul 21, 2013 9:30 pm

That was pretty careless ! :o
thanks for letting us know the problem is now resolved.
Cheers.

TUFTYNUTKIN
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Bike(s): ST70 LADY DAX
Location: Saffron Walden
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Re: problem with lights

Post by TUFTYNUTKIN » Sun Jul 21, 2013 9:46 pm

Hi
Its good when members let us know when issues are resolved
Regards Tufty

Wayneyboy
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Re: problem with lights

Post by Wayneyboy » Sun Apr 04, 2021 5:39 pm

Hi regarding these three out puts, green, yellow and pink, do they have the same volts from the lighting coil, my three wires two have 5/6 volts and one as 10 volts, thank you

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