Voltage Issue

[agilebda]

Hey guys. Where would you check for voltage issues? Brake lights are dim, headlight is fine, engine wouldnt crank over or even turn. Not enough amperage. I have tried two brand new batteries and still the same issue. Connections look good, ground and positive. Let me give you a little history on what happened recently: I was riding through town, stopped in a store for 10 mins, jumped back on bike and wouldnt crank. Immediately thought dead battery. Removed the battery and it was too hot to touch. Battery was puffed and expanded so I thought the voltage regulator needed replacing, which I gladly did. Purchased new battery, and she still wouldnt crank over. (Actually she started once when i installed the 1st new batt), the she wont roll again. Brake light is dim, headlight is fine, indicators are weak, pull the brake lever to hit the starter and the entire dash lights up with all indicators and accessories illuminated on the display. The only other thing I can think of is the little circular starter relay that the positive wire and negative wire attach to before going to the starter motor. What are your thoughts?

[mousejunks]

You've replaced the battery and voltage regulator which should have ruled out any electrical power problems. The first incident when the battery swelled up sounds like it shorted out internally and gassed for whatever reason. Does the bike turn over when you press the start button?

Do you have a voltmeter or multimeter? What is the resting voltage of the battery (should be at least 12.6V) and under load (e.g. headlights on). Then when it can run, check the voltage again (about 14-14.5 volts). 

[Ruffus]

@agilebda, a new battery does not mean neccessarely it's a functional battery. Pls try those steps:
- press brake levers, brake light shows?
- charge new battery or take jumpstart cables/ car
- attach its minus cable to your scoots motor block
- touch with its plus cable scoots starter plus on top...does it crank ?
If cranks either your starter solenoid or cabling between solenoid and starter is failing

NO cranking, your starter motor is rotten
- there is a fat ground cable close to your starter motor, attached with a 8mm bolt, check whether this is still in place and not corroded off.
 Pls give a feedback.
This cable looks suspiciousely like the ground to motor casing to me.
There is somewhere close to the starter motor a thread of 6mm where it should belong to.
Or just fix it somehow to the motor casing and try to start.

[agilebda]

You've replaced the battery and voltage regulator which should have ruled out any electrical power problems. The first incident when the battery swelled up sounds like it shorted out internally and gassed for whatever reason. Does the bike turn over when you press the start button?

Do you have a voltmeter or multimeter? What is the resting voltage of the battery (should be at least 12.6V) and under load (e.g. headlights on). Then when it can run, check the voltage again (about 14-14.5 volts).

Thanks Mousejunk. I installed a new batt and the bike started once. Shut it down after a few mins and she wouldn't turn over again due to what it appears to be weak voltage. I will test voltage and check wiring today. Could be two new batteries that were dead but I can be wrong. I hit the starter and have my hand on the starter relay, and I feel the click like a plunger. I will check the negative and positive leads the entire way through. I will keep you all informed. Thanks for the quick replies.

[agilebda]

Thanks Mousejunk. I installed a new batt and the bike started once. Shut it down after a few mins and she wouldn't turn over again due to what it appears to be weak voltage. I will test voltage and check wiring today. Could be two new batteries that were dead but I can be wrong. I hit the starter and have my hand on the starter relay, and I feel the click like a plunger. I will check the negative and positive leads the entire way through. I will keep you all informed. Thanks for the quick replies.

Check what I found today guys. Could be the intermittent start issue.?

[CROSSBOLT]

Check what I found today guys. Could be the intermittent start issue.?

That could be part of it!

[agilebda]

Thanks Crossbolt. I realized that new batteries have to be charged after the acid is installed. I think that my automotive 110v charger has an issue as well. I should have posted this vid on my very 1st post.

https://drive.google.com/file/d/1uwdjR9x7Z7BaT4wsfzTMB8NPe3eJwsLc/view?usp=drivesdk

Talking a lunch break and will come back to the project later.

[agilebda]

So I checked the wiring and sll looks good instead of this one wire which is grounded to the frame next to the coil labeled KYMCO D403. The other end of this cable had a connector which looks like it connects to the battery. It was connected to nothing at all.
So this is how my stuff is wired up for some reason....Negative from battery is grounded to a bolt on the engine casing. The positive lead goes from battery to relay to the starter motor. Where does this D403 wire with the battery fitting lead go to?? This is what stomps me.

[mousejunks]

Thanks Mousejunk. I installed a new batt and the bike started once. Shut it down after a few mins and she wouldn't turn over again due to what it appears to be weak voltage. I will test voltage and check wiring today. Could be two new batteries that were dead but I can be wrong. I hit the starter and have my hand on the starter relay, and I feel the click like a plunger. I will check the negative and positive leads the entire way through. I will keep you all informed. Thanks for the quick replies.

So the click means the solenoid is engaging but the lack of turning over means the starter motor isn't turning over. The pic above with the rust is a huge sign that the starter motor connection is bad. Easy solution is just to clean it and reattach.

[CROSSBOLT]

So I checked the wiring and sll looks good instead of this one wire which is grounded to the frame next to the coil labeled KYMCO D403. The other end of this cable had a connector which looks like it connects to the battery. It was connected to nothing at all.
So this is how my stuff is wired up for some reason....Negative from battery is grounded to a bolt on the engine casing. The positive lead goes from battery to relay to the starter motor. Where does this D403 wire with the battery fitting lead go to?? This is what stomps me.

The usual route for battery negative is:
1. Battery - to frame gound point (rusty post and nuts in your picture)
2. Starter ground to rust nuts in picture (or engine case ground to rust nuts)

Usual Battery + route:
1. Battery+ to start relay heavy post (fat red wire) (skinny red wire off that same post to fuse box).

[agilebda]

Hello Guys, check over everything today. My cables negative and positive have good continuity throughout. I tested the started with jumper cables to my truck battery and works fine.
Funny how I press the brakes and the dash lights up without pressing the starter button. Could there be something around the brake levers that's causing the voltage drop? I ordered the batteries and they came by air. Could that have anything to do with anything? Added battery acid to the battery per the instructions, left it for 1hour, then charged it for an hour.
What else can I check on this scoot?

[agilebda]

@agilebda, a new battery does not mean neccessarely it's a functional battery. Pls try those steps:
- press brake levers, brake light shows?
- charge new battery or take jumpstart cables/ car
- attach its minus cable to your scoots motor block
- touch with its plus cable scoots starter plus on top...does it crank ?
If cranks either your starter solenoid or cabling between solenoid and starter is failing

NO cranking, your starter motor is rotten
- there is a fat ground cable close to your starter motor, attached with a 8mm bolt, check whether this is still in place and not corroded off.
 Pls give a feedback.

Hello. Tried all of this. Ground is not corroded off. Brake lights come on but very dim. I'm inclined to thing I have 2 flat batteries that arrived. Dead cells. Headlights are fine. When the brake levers pressed all goes dim. Everything goes dim.

[agilebda]

The usual route for battery negative is:
1. Battery - to frame gound point (rusty post and nuts in your picture)
2. Starter ground to rust nuts in picture (or engine case ground to rust nuts)

Usual Battery + route:
1. Battery+ to start relay heavy post (fat red wire) (skinny red wire off that same post to fuse box).

Thanks Karl, I will check that all out.

[agilebda]

Thanks for all your help guys. I found the silly little culprit. It was a sticky faulty start switch. Swapped it out, charged the battery again and she's been running great all day. Once again thanks to all who shared their input.

Toni

[Ruffus]

Great to hear it works👍👍👍