2009 S 200 Headlight failure - Both High and Low beams

[Patrick]

Just the headlights don't work.  Turn signals, horn, dashboard and brake lights all OK.  Cracked the top and accessed the headlights.  They work when connected to the battery.  High low switch appears to work.  So I thought the problem was in the so called headlight relay which I show on my parts list as "Control ASSY Unit Lighting - 3860A-LCD3-EO2.  Got a new one from my Kymco dealer at a cost of $65. Installed and problem unchanged.  No headlights but all other lights work.
My scooter has 5,000 kilometers on it.  Not much when spread over 10 years.  No accidents. Knocked over once years ago while parked.  Mostly kept indoors and fluids kept up. Never really had a problem until now.  Scoot starts and runs and I guess I'm OK in daylight but could not pass state inspection next year without headlights.
I really can't see why a sudden problem would develop in the wiring harness.  I think it's a component and I don't konw which one. Any ideas?
I appreciate any help.
MOre testing done.  When I stripped a small part of the insulation from the four wires going into the relay I found the problem.  Two of thesefour wires come from the high low switch - one for the high beam and one for the low and two go to the headlights - one for the high beam and one for the low. When I took a wire and jumped the high beam wire from the switch with the high beam wire going to the headlight and turned on the ignition switch the light came on.  Same with the low beam.  So I can jump the wires, bypass the relay and my headlights work.  I got a bad part from the dealer.  Now I have to get a relay that works or remove the relay and wait for something to burn up.

[Tromper]

Heck, beyond cleaning all connections, especially to the CDI, you've done the main thing I'd have tried.

There's a way to bypass the LCM completely that I'd have to look up or farm out cuz wiring ain't my super power.

Have you tried that?

[CROSSBOLT]

Relays?

[Patrick]

Thanks for the ideas.  I have spoken to an career auto mechanic and a commercial electrician.  I am beginning to think that the problem is a failure of the ground connection between the headlights and ground.  I am going to look at the wiring harness connections right at the headlights and see if I can strip  the insulation off the ground wire.  I have some three foot lengths of 20 guage wire with alligator clips  on both ends.  I will clip one end to the bare wire I stripped and the other end to a bare part of the frame and see if that works.

I do have this neat electrican's tool I got to strip wire that clamps and pulls the the wire insulation apart leaving exposed bare wire.  A big step up from my old wire cutters but in common use these days.  It will let me use my DC voltage light tester where ever I need.  So we will see if a failed ground connection is the problem.  If it's not the ground it is going to get wild.   I am willing to jump wires and cut and solder if I need to. I'll go slow but I have been told the bike is worth less than paying a serious mortorcycle mechanic $70 an hour while he takes the wiring harness apart.

I will report back.

[Iahawk]

looking forward to hearing how this turns out...good luck.

[Patrick]

More testing done.  Showed pictures of the plug ends to my mechinic buddy.  He suggested two things.  One strip a small part of the wires leading into the plugs - no cutting - and measure resistance from that wire to the other end of the wire in the actual male end of the plug - removed from the relay and power off. That should tell you if the plug itself has failed because of increased resisitance where the metal pieces at the end of the wire have mated with the metal pieces in the plug.   Did that and no resisitance is showing using my 2 meg resitance scale on the multimeter.
Second idea/observation was that the two conductor plug into the relay (ground and power) had brown discoloration around the red or power conductor showing in the plug. Brown discolored plastic about 1/2 inch long. Possible heat damage to the metal conductors in the plug.  Next test will be to assemble the relay and put the 4 couductor plug in place.  Instead of the two conductor plug I will use two paperclips (separated from each other electrically) and several of my short jumper cables to jump the female conductors that receive the two wires to, respectively, ground and a direct jump from the negative terminal of the battery.  IFFFFF the headlights work then the plastic plug must be replaced.  If not then I will try and understand the various resistance tests shown in the shop manual for this relay.  Maybe  I got a defective new part from my Kymco dealer.
Will do that in 10 days or so when we return after Thanksgiving.  Meantime Happy Holidays to all.

[abobotek]

The headlight controller may be bad, or perhaps it isn't receiving a pulse from the ignition module.  The headlight controller uses the lack of a pulse to turn off the headlights at low RPMs.  You can check for the pulse with a scope if you have one. 

[CALtd-SLO]

Instead of stripping wires, think about using vampire connector.