Kymco 150 - no headlights, turns over, won't start

[skishades]

While installing a top case which had a brake light, I shorted out the wire to the box. A fuse blew. I changed the fuse, but since then, my headlights don't come on with the switch and the engine won't start. The engine turns over, but won't start. The kill switch is not on btw. I'm having trouble diagnosing the problem since I can't figure out what would have hurt the headlights by shorting out the brake light. I can trace the wire directly to the fuse that blew from the brake light but the headlights are not on the same line. All the dashboard lights, turn signals and brake lights work with no problem, when the key switch is turned on. The headlights just don't come on and I think that problem relates to its inability to start. Could it be the CDI? How do I check for CDI functionality?

Update:
Ok... I have figured out several of the problems. First, the short did something to my alarm. My alarm did have the ability to disable the starter, but that was the first thing I disabled after the bike wouldn't start. I traced each wire, and sometimes, I would get a spark. Found the short in the last wire connected to the alarm. The alarm shorted out in its electronic brain (the expensive part) and was effectively draining the charge from the CDI preventing it from starting (note this wire was not connected to the starter, just connected to a powered line but was then permanently grounding the whole system). Upon removal, the bike started just fine. Now the headlights are another issue. While the bike was disabled, I replaced all the lights (turn signals, dash, license plate and headlights) with LEDs. With the alarm draining the power from the CDI, the CDI was pulling power from the headlights in an effort to start. The CDI has a wire to the electronic control module on a KYMCO 150 that "kills" the lights to have more available power when starting the bike. Since I had changed the lights, then pulled the alarm completely out, the lights came on after starting (not with the key as it did originally) but wouldn't stay on when revving. They only came on at idle. I checked the CDI, and ECM and both were running correctly. The LED headlights were not pulling enough amps unless the engine was at idle so when gas was given, the ECM cut power thinking there was nothing connected. I had two separate problems with an intermittent short. To sum up, the alarm drained the starter and the headlights originally, the new LED's didn't pull enough amps to be detected but were installed before the first problem was solved, removal of the alarm fixed the starter and bypassing the ECM fixed the headlights for the LEDs.

[jazzman]

The CDI has nothing to do with the headlights, but let me ask this on your scoot if you turn the key on do you have a switch that turns on the lights OR does the motor have to be running.

[jazzman]

I believe you are correct BONG, on the KYMCOs I think there is a wire coming off the Battery that splits out and each split has a fuse on it.

[macktheknife]

Check you PM.

[skishades]

There are 3 fuses next to the battery (2 7w and 1 30w). I have had all the plastic off this scoot at some point, they are the only fuses original to the scooter. The CDI does have a wire to the headlight control assay. When trying to start the scoot, it reduces power to the lights (they dim) to give extra power to the ignition coil. The lights come on automatically when you turn the key on... there is no off switch for them when the key is turned on. I have checked and tested all 3 fuses and they are all functional and intact. Currently, when I turn the key on, the headlights do not work at all (highbeam or normal). There is no power going to them. The switches in the dash all work (as in I have tested each wire coming off them and they show power or ground correctly). My scoot is a Kymco Super 8 150cc. The only wire that goes to the headlight and the brakelight and the CDI is the ground. The fuse that blew goes to the CDI and key switch (both), the other fuse goes to the light control, the third use is a 30A and did not blow. I replaced the light control box which did nothing. The CDI has a wire to the light control box to "pull" extra power for the ignition coil and it also sends power to the ignition coil and spark plug directly. The CDI however, does not have a wire to the starter itself, which is why I think it turns over, but won't start. My best guess is its drawing or grounding all the power from the light control box but not building any power up in its capacitor, so it can't sustain ignition.

[skishades]

When I disconnect the wire from the light control box to the CDI, I still have no power to the headlights, even though the light control box has power directly from the battery (which is why I originally replaced the light control). I think the CDI may also "send" power when it doesn't need it (like when the power is off or the engine is already running) and only "take" power when it needs that extra boost for starting.

[scootercapecod]

Here's a few thoughts (and I hope they help instead of seem sarcastic) I have when reading the thread. Assuming you that the voltage regulator is good you shouldn't have any trouble and knowing that the scooter is a kymco, I have to assume that there must be a kill switch on the side stand and if it's not up, then the scooter wont start. Also, the CDI is an AC CDI (most GY6 or clones are) so that said your headlights won't come on until the motor is running (however, your dash panel lights should come on when you turn the key on). Unless you've smoked the CDI or didn't correct the wiring short (thus causing the brake light not to work which could be a starting issue as well) it's strange that you're not getting at least ignition. Have you tried testing for current off the coil? or a safer method, just checked for spark? Trust me when I tell you that touching a charged coil can be a shocking experience (haha). It seems like you have some wor ahead of you but let us know what (if you do find out) was the issue

[skishades]

There is no side stand switch on this Kymco. The headlights have always come on when I turn on the key before (they dim as you turn the engine over... at least that is how it's supposed to work). The wiring short was on an attachment to the scooter and has been fixed as evidenced by the brake lights working normally once the fuse was replaced. I will check the spark but only the CDI is between the lights and the spark plug (there is no other "direct" connection)... if there was no spark... it could still be the CDI as the fuse for the brake light power is not connected in anyway (except through the CDI) to the charged coil. The CDI gets power from the 30w and the 7w (only when its starting though for the 7w) Or its 2 completely different problems and aren't related... I have repair manuals and wiring diagrams for getting to any part... I just can't seem to find the actual problem. Still awaiting a new CDI though... another week to test that.